Just picked up a 1990 cherokee. And was wondering if theres anything i should look for. I believe it a renix 4.0 liter. How much of a differnece is there etween this and my 1998 i had.

 

It's a Renix for sure. Lots of differences.

 

It would be easier if you told us what the difference since there were your Jeeps you had them in your possession.

 

Nice chat. Ill have to do some research.

 

Right there in my signature is a Wikipedia link with all sorts of links in it.

Crusier there^, did the 4 main Renix writeup's below. The rest is just some stuff I found.


https://www.cherokeeforum.com/f51/he...ix-links-1397/


Nov. 25, 11 Jeep Links and Articles. There is some non-renix. For example Renix has no ASD relay. The fuel pump relay does...things....

If you hold the key over, and jiggle the shifter in park or neutral and it starts, it's your NSS. http://bc4x4.com/tech/2010/jeep-neut...ty-switch-nss/
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Clutch Writeup 97 ***
http://borntourist.com/gallery2/v/mo...tch/?g2_page=1
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Renix Hybred to HO
https://www.cherokeeforum.com/f2/bro...116880/index2/
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Disco Clip lock
https://www.cherokeeforum.com/f51/fr...ss-91-a-38629/
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OBD II Codes
http://www.check-engine-light.com/trouble-codes
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Freedgr”s Renix
http://www.eriejeeppeople.com/Jeep_t...ion_manual.pdf
20 Renix links
https://www.cherokeeforum.com/f51/he...ix-links-1397/
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Renix 88 http://jeepgarage.free.fr/OWN/4.0l%20cec%20system.pdf
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Index 4.0 Dizy http://ezinearticles.com/?How-to-Ind...tor&id=1357018
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Slick's, Chad's, Renix sensor testing info.
http://www.lunghd.com/Tech_Articles/...iagnostics.htm
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2357s are the heavy duty/brighter version of the 1157 combination tail/signal light bulb.

795s are a halogen single filament bulb replacement for the old 1034s like you have in your reverse lights. Much brighter.
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Adjustable MAP http://go.jeep-xj.info/HowtoMAPsensor.htm
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NSS http://www.boyandjeep.com/tech-artic...switch-rebuild
http://go.jeep-xj.info/HowtoNSSrebuild.htm
http://bc4x4.com/tech/2010/jeep-neut...ty-switch-nss/
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Slotted 89 Renix CPS http://autorepair.about.com/library/a/1i/bl534i.htm
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CPS & Harness bypass there http://www.bc4x4.com/faqs/yj.cfm?cat=5&faqid=164
Chad's, Bunch of prodcedures. Blower replace....http://www.lunghd.com/On_Site_Tech.htm
OIL FILTER ADAPRER O RINGS http://www.myjeepxj.com/cherokee-rep...filter-adapter
Oil filters/info http://minimopar.knizefamily.net/oil...reference.html
Oil Filters.Revieled. http://minimopar.knizefamily.net/oil.../opinions.html
Heads, porting, injectors used. FUEL PRESSURE.
http://www.jeep4.0performance.4mg.com/tech_specs.html
a can of BG 44K in the tank is superbly effective in cleaning your fuel system including injectors, back of valves etc.
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Possibly is the ECM then. If you're going to the JY, get one out of a 1989 or 1990 with the part number ending in 428.
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T-Case shifter, (Custom) http://www.bsfab.net/?p=26
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Stereo’s Allarm, Remote http://www.the12volt.com/
8899 Larado YOUTUBE__CPS http://www.cherokeetech.com/VBull/sh...agnosis-Videos
http://www.cherokeetech.com/VBull/sh...agnosis-Videos
+++++++++++++++++++=============================== ======================
Cat Backpressure Vac Test
http://www.aa1car.com/library/converter.htm
++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++
AW4 SWAP -TCU Secrets?
http://www.stu-offroad.com/engine/aw-4/aw-4-2.htm
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# @ Drivers side top edge

The heads that had trouble were the early #0331 heads (1999-2001WJ/TJ, 2000-2001XJ) before they were revised in late 2001 (revised heads have the "TUPY" foundry mark.)

1998 will have the #0630 head, which is typically subject to uncommon individual defects rather than a class-affecting problem.
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LITTLE BALL, LONG GREEN, TEE YOUR WHITE BALL...................................

Light Blue, Light Green, , Tan, Yellow, White, then Black are the injector wire color codes I think. Maybe that could be it.
If you know the pair in the middle is right, you only need to check one on each end.
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++++++++++++++++++++++++++++++++++++++++++++++++++ ++++++++++++++++++++++


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You can try this. I hear sometime in 97 it no longer works.
1984-1990 w/AMC engine are pre-OBD.

1984-1986 w/GM V6-173 are OBD-I (GM control setup.)

1991-1995 are OBD-I (Chrysler)

1996-2001 are OBD-II (Chrysler)

The "Key Tricks"
Older (OBDI) models - Start with the ignition off. Within five seconds, switch the key on, off, on, off, on. ("On" is NOT "Start" and "Off" is NOT "Lock"). The "check engine" light will flash. Count the flashes. Each code is a two digit code, so a (for example) 23 would be FLASH FLASH (pause) FLASH FLASH FLASH (long pause). It will never flash more than 9 times, so watch for those pauses!

Newer (OBDII) models - Put the key into the ignition, push down the odometer reset button, then turn the key to RUN with your finger on the button - and then release the button. The odometer will go through 1111111 through 999999, then display the car's serial number. It will then show the error codes (it might show them starting with P). If this method does not work, try the OBDI method.
On YOUR CPS, I recently found this link on testing the later, OBD II CPS, which may well apply to yours. I haven't tried it, don't know anyone who has. It looks like he's verifying 1/2 a volt, (aka.5v or 500 Mil.Volts), presumably AC, (with a true RMS meter), (back-probing, with it connected), at his third (Red) wire. (not the ground, and not the 5V-DC sensor feed). I don't know what % difference I would expect from my "cheap-o-meter", as opposed to the true RMS, but it might not be much. http://www.cherokeetech.com/VBull/sh...agnosis-Videos
================================================== ========
Renix.
Resistance chart for both Coolant Temperature Sensor
-and-
Manifold Air Temperature
Coolant Temperature and Manifold Air Temperature Sensor Resistance Values
Approximate resistance your meter should show at the temperature shown in the chart.
NO resistance indicates a 'short' to ground - can be the sensor but will usually be a wire where the insulation has been abraded.
INFINITE resistance indicates an 'open / broken circuit. Can either be a broken wire or a bad sensor.
Degrees Fahrenheit
Degrees Celcius
Resistance in Ohms
-40
-40
100,700
0
-18
25,000
20
-7
13,500
40
4
7,500
70
20
3,400
100
38
1,600
160
70
450
212
100
185



Originally Posted by PM from 5-90 To 89 Lurato

The RENIX TPS output is not an absolute, neither are absolute resistance readings necessary in the TPS proper.

TPS output voltage should be 17% of input voltage, I will invariably use the manual transmission test outlined in the FSM (1990 FSM p. 8D-33.) This works on vehicles with the AW4 as well, and I consider it to be more reliable than the procedure for the automatic - since the automatic uses the "transmission side" to test, and the automatic TPS is two sensors in one body, a "good" test on the transmission side is not necessarily a "good" test on the engine side. And the engine side is more important.

Begin by measuring the input voltage to the TPS, between pins A and B on the three-pole cnx. Should be ~5.0VDC (experience shows that 5.0VDC +/- 0.5VDC is about right, so 4.5-5.5VDC. It's a regulated supply, and regulators do deteriorate with age.)

Calculate 17% of the input voltage. For correct 5.0VDC, that would be 0.85VDC. For, say, 4.83VDC, that becomes 4.83 x 0.17 = 0.8211VDC. (Yes, use a digital voltmeter, unless you're very experienced with an analogue and have one known to be reliable. It's that important.)

Backprobe pins B and C (positive lead in C) and read output voltage at closed throttle. Loosen the two screws, adjust to reach the figure calculated earlier (17% of input.) Hold the TPS in place (usually, pressing with your thumb will do) and tighten the screws to retain the adjustment. I like to dab a bit of fingernail enamel on these screw threads as an ersatz threadlocker - it has a few advantages:
- It's actually less strong than even LocTite #222, so you don't risk snapping off the screws
- It's just as waterproof.
- It does a better job of coating the threads.
- It may be "gently broken" to allow for adjustment, and will retain the screws without needing to reapply.
- You have a longer initial work time.

However, it is vital that you not use a fixed value for calibration - it is only 0.85VDC nominal output if the reference voltage signal supplied is 5.0VDC! A reference voltage of 4.5-5.5VDC is considered "acceptable," I'd start thinking about a replacement ECU below 4.25VDC.

Any main ground should experience a resistance of less than two ohms (good condition) or even as much as ten ohms (average condition) between that point and the ultimate ground point (battery negative terminal,) depower circuit to measure this. (Removing the battery positive lead is typically sufficient.)

For a function test of the TPS, an analogue ohmmeter is required. Absolute resistance values are not necessary, nor are they given.

What you do is you disconnect the three-wire plug, connect in to the TPS side for pins A & C or B & C, and then slowly and smoothly sweep the wiper arm on the sensor. The resistance reading should vary smoothly as you move the wiper arm - adjust your ohmmeter range setting until you get a reading that makes sense and varies with the position of the wiper arm. You can not use the typical DMM for this test, as a DMM has buffer circuits inbuilt into it that will work to stabilise a reading - and cause a delay in showing a reading change. Analogue ohmmeters do not have buffer circuits, and respond instantly (to demonstrate, set a DMM and an analogue multimeter to the 200VAC range, and connect both to a house outlet. You'll probably see the needle on the analogue waver slightly, while the digital tends to "seek." The analogue response is instant - and knowing this is the first step toward using an analogue multimeter correctly for diagnosis and troubleshooting. I've been using them for thirty-odd years, so I've gotten used to it. I ignore it if I don't need to know, and process it if I do. I've never gotten rid of my analogue, so I have an analogue and a digital handy.)

TO MAKE BACKPROBE PINS:
- Go to your wife's/girlfriend's/SO's/mother's sewing kit.
- Find the two longest, heaviest straight pins in there (quilting pins are good, hatpins are better.)
- Ask for them nicely. (If you end up having to, just go to the craft store and pick up a packet.)
- With a stone (like you'd use to sharpen a blade,) blunt the point of the pins. You want to round it off nicely with no burrs - the lack of burrs will help to preserve insulation and seals. You should be able to press the tip against your skin without penetrating.

The pins slide in the backside of the connector alongside the wire, so you can take a reading without disconnecting (which sometimes eliminates the possibility of taking a useful reading.)

Backprobe pins may also be purchased at electronic supply houses, but they're cheaper to make and easy enough, and you can make a dozen or so for less than what purchasing two would cost. Just don't let the metal bits touch once you've got them inserted - I've made a set and found heat shrink small enough (in various colours) to have a set of a dozen or so that are colour-coded - I used floral pins (about 2m/m thick, about 3" long) and left the 3/4" or so nearest the point uncovered. The heat shrink was cut short enough and located so that I can attach a small crocodile clip or a five-way test lead clip directly to the pin shaft, but the rest of the exposed metal is covered (and the heat-shrink helps to colour-code the things so I can keep them straight on sight. I should probably start making more sets...)


And Cruiser's Renix TPS adjustment.

Here's another set of TPS instructions.They're not better, just different. And certainly nowhere as comprehensive as 5-90's. I wish I'd seen his before I put the work into these.

RENIX TPS ADJUSTMENT
Before attempting to adjust your TPS be sure the throttle body has been recently cleaned.
It's especially important that the edges of the throttle butterfly are free of any carbon build-up.
IMPORTANT NOTE: Using the positive (red) lead of your ohmmeter, probe the B terminal of the flat 3 wire connector
of the TPS . The letters are embossed on the connector itself.
Touch the black lead of your meter to the negative battery post.
If you see more than 1 ohm of resistance some modifications to the sensor ground harness will be
necessary. The harness repair must be performed before proceeding.
I can provide an instruction sheet for that if needed.
MANUAL TRANSMISSION:
RENIX manual transmission equipped XJs have a three-wire TPS mounted on the throttle body.
This manual transmission vehicle TPS provides data input to the ECU. The manual transmission
TPS has three wires in the connector and they're clearly embossed with the letters A,B, and C.
Wire "A" is positive.
Wire "B" is ground.
Key ON, measure voltage from "A" positive to "B" ground by back-probing the connectors..
Note the voltage reading--this is your REFERENCE voltage.
Key ON, back-probe the connector at wires "B" and "C". Measure the voltage. This is your
OUTPUT voltage.
Your OUTPUT voltage needs to be seventeen percent of your REFERENCE voltage. For
example: 4.82 volts X .17=.82 volts. Adjust the TPS until you have achieved this percentage. If
you can't achieve the correct output voltage replace the TPS and start over.
AUTOMATIC TRANSMISSION:
RENIX automatic transmission equipped XJs have a TPS with two connectors. There is a flat three-
wire connector, same as the manual transmission vehicles have, and it is tested the same as the
manual transmission equipped vehicles--FOR ENGINE MANAGEMENT RELATED ISSUES.
However, the automatic TPS also has a square four-wire connector clearly embossed with the letters
A,B,C, and D. It only uses three wires and provides information to the Transmission Control Module.
Key ON, measure voltage between "A" positive and "D" ground. Note the voltage. This is your
REFERENCE voltage.
Back-probe the connector at wires "B" and "D". Measure the voltage. This is your OUTPUT
voltage. Your OUTPUT voltage needs to be eighty-three percent of your REFERENCE voltage.
For example 4.8 volts X .83=3.98 volts. Adjust the TPS until you have achieved this percentage.
If you can't, replace the TPS and start over.
So, if you have an automatic equipped XJ your TPS has two sides--one side feeds the ECU, and
the other side feeds the TCU. If you have TRANSMISSION issues check the four-wire
connector side of the TPS. If you have ENGINE issues check the three-wire connector side of
the TPS.
For those with a MANUAL TRANSMISSION--the TPS for the manual transmission XJs is
stupid expensive. You can substitute the automatic transmission TPS which is reasonably priced.


Renix CPS Testing and Adjusting
　
　
Renix CPSs have to put out a strong enough signal to the ECU so that it will provide spark.
Most tests for the CPS suggest checking it for an ohms value. This is unreliable and can cause some wasted time and aggravation in your diagnosis of a no-start issue as the CPS will test good when in fact it is bad.
The problem with the ohms test is you can have the correct amount of resistance through the CPS but it isn’t generating enough voltage to trigger the ECU to provide spark.
Unplug the harness connector from the CPS. Using your voltmeter set on AC volts and probing both wires in the connector going to the CPS, crank the engine over. It won’t start with the CPS disconnected.
You should get a reading of .5 AC volts.
If you are down in the .35 AC volts range or lower on your meter reading, you can have intermittent crank/no-start conditions from your Renix Jeep. Some NEW CPSs (from the big box parts stores) have registered only .2 AC volts while reading the proper resistance!! That’s a definite no-start condition. Best to buy your CPS from Napa or the dealer.
Sometimes on a manual transmission equipped Renix Jeep there is an accumulation of debris on the tip of the CPS. It’s worn off clutch material and since the CPS is a magnet, the metal sticks to the tip of the CPS causing a reduced voltage signal. You MAY get by with cleaning the tip of the CPS off.
A little trick for increasing the output of your CPS is to drill out it’s mounting holes with the first drill bit that just won’t fit through the original holes. Then, when mounting it, hold the CPS down as close to the flywheel as you can while tightening the bolts.
　
Revised 11-29-2011


Renix Ground Refreshin
The Renix era XJs and MJs were built with an under-engineered grounding system for the engine/transmission electronics. One problem in particular involves the multiple ground connection at the engine dipstick tube stud. A poor ground here can cause a multitude of driveabililty issues, wasted time, and wasted money replacing unnecessary components.
The components grounding at the dipstick tube stud are:
Distributor Sync Sensor, TCU main ground, TCU "Shift Point Logic", Ignition control Module, Injectors, ECU main ground which other engine sensors ground through, Oxygen sensor, Knock Sensor, Cruise Control, and Transmission Sync signal. All extremely important stuff.
The factory was aware of the issues with this ground point and addressed it by suggesting the following:
Remove the nut holding the wire terminals to the stud. Verify that the stud is indeed tightened securely into the block. Scrape any and all paint from the stud’s mounting surface where the wires will attach. Must be clean, shiny and free of any oil, grease, or paint.
Inspect the wire terminals. Check to see that none of the terminals are crimped over wire insulation instead of bare wire. Be sure the crimps are tight. It wouldn’t hurt to re-crimp them just as a matter of course. Sand and polish the wire terminals until clean and shiny on both sides. Reinstall all the wires to the stud and tighten the nut down securely.
While you’re in that general area, locate the battery negative cable which is fastened to the engine block just forward of the dipstick stud. Remove the bolt, scrape the block to bare metal, clean and polish the cable terminal, and reattach securely.
Another area where the grounding system on Renix era Jeeps was lacking is the engine to chassis ground. There is a braided cable from the back of the cylinder head that also attaches to the driver’s side of the firewall. This cable is undersized for it’s intended use and subject to corrosion and poor connections at each end.
First off, remove the cable end from the firewall using a 15mm wrench or socket. Scrape the paint off down to bare metal and clean the wire terminal. Reattach securely.
Remove the other end of the cable from the rear of the head using a 3’4" socket. Clean all the oil, paint and crud from the stud. Clean the wire terminal of the cable and reattach securely.
A suggestion regarding the braided cable:
I prefer to add a #4 Gauge cable from the firewall to a bolt on the rear of the intake manifold, either to a heat shield bolt or fuel rail bolt. A cable about 18" long with a 3/8" lug on each end works great and you can get one at any parts store already made up. Napa has them as part number 781116.
A further improvement to the grounding system can be made using a #4 cable, about 10" long with 3/8" terminals at each end. Attach one end of this cable to the negative battery bolt and the other end under the closest 10mm headed bolt on the radiator support just forward of the battery. Napa part number 781115.







Renix Jeep ICU/Coil contact refreshing
　
　
The contacts between the coil and the ICU on your Renix Jeep can become corroded and loose causing a complete or intermittent no-start condition. I recommend the following procedure as a maintenance precaution to insure this is eliminated as a possible cause now and in the future.
The coil is attached to the ICU by two T20 Torx bolts. Remove these two bolts and lift the coil up off the ICU. You will see 2 pins and 2 sets of contacts. Clean both the pins and springy contact pieces with a good electronics cleaner.
Squeeze the springy contacts closer together with some needlenose pliers. Apply some dielectric grease to the contacts and bolt the coil back on to the ICU.
While you’re right there unplug the connectors from the ICU and inspect the pins in the harness connector. Make sure the pins are not retracted into the connector. Spray out the connector and the receptacle of the ICU with the same good electronics cleaner you used earlier. Apply dielectric grease to the connectors and plug them back in.
I feel this procedure should be performed at least once in the lifetime of a Renix Jeep.
　
Revised 11-29-2011
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Renix Jeep C101 Connector Refreshing
　
The C101 connector on 1987 and 1988 Renix Jeeps was a source of electrical resistance when the vehicles were new. So much so that the factory eliminated this connector in the 1989 and 1990 models. The factory recommended cleaning this connector to insure the proper voltage and ground signals between the ECU and the fuel injection sensors. We can only imagine how this connector has become a larger source of voltage loss and increased resistance over a period of almost 25 years. The C101 connector needs to be cleaned at least once in the lifetime of your vehicle. Chances are it’s never been done before.

Almost every critical signal between the engine sensors, injectors, and the ECU travel the path through the C101.
The C101 is located on the driver’s side firewall above and behind the brake booster. It is held together with a single bolt in it’s center. To get the connectors apart, simply remove the bolt and pull the halves apart. You will find the connector is packed with a black tar like substance which has hardened over time.
Take a pocket screwdriver or the like and scrape out all the tar crap you can. Follow up by spraying out both connector halves with brake cleaner and then swabbing out the remainder of the tar. Repeat this procedure until the tar is totally removed. This may require 3 or more repetitions. Wipe out the connectors after spraying with a soft cloth.
If you have a small pick or dental tool tweak the female connectors on the one side so they grab the pins on the opposite side a bit tighter. Apply a true dielectric grease, not the stuff that came with your brake pads, to the connection and bolt it back together.
　
　
Revised 11-29-2011
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AC voltage CPS test; Small clips on the meter leads really helps.

Unplug the connector at the back of the manifold with wires going down to the bell-housing/cps.
Probe the two wires to the cps with the meter set on AC volts. (a 200 scale on mine).
Crank the engine and note the voltage. (jump it if your battery is low)

Mine somehow works with only .3 my wiring/grounds must be pretty spiffy. .5 seems to be a good mark. One article talked of .5 to .8.

If it's low you can modify the cps. With the next largest bit that won't fit in the hole, enlarge the hole's in the bracket just a tad. Now when mounting it's crucial to maintain firm downward pressure on it while tightening the bolts. An assistant could help with that from above.
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Originally Posted by ET JEEP
There is a very simple test you can do to help isolate where the problem resides.

When the starter does not engage the problem is either the solenoid/starter, the electrical starting circuit or the battery cable that attaches directly to the starter.

You need to start with a fully charged battery, clean and tight connections at the battery, ground and starter. You need good battery cables.

When the starter does not engage do this. Disconnect the wire going to the solenoid on the starter. Get a helper to hold the ignition switch to the start position. The engine will not crank as the solenoid wire is disconnected. Now with a volt meter test for voltage on that wire. It should read battery voltage. Test the battery for a voltage reference.

If the wire has battery voltage then the problem is in the solenoid/starter or battery cable. If the wire does NOT have battery voltage the problem is in the electrical starting circuit.

The electrical starting circuit consists of the fuse, ignition switch, wiring, engine starter relay, NSS and a good ground thru the NSS.

When you turn the ignition switch to start, electrical power goes from the fuse to the ignition switch, thru the wires to the relay, thru the relay to NSS, thru the NSS to ground. This activates the relay. With the relay activated, battery power is connected to the solenoid wire which in turn engages the starter.

There are checks you can do to test the relay contacts (pins 86,85,30,87).

The usual problem is the NSS. But it could be in some other part of the circuit.

To test that the starter does crank the engine you can run a wire from batttery positive and touch the solenoid terminal. The starter should engage and crank the engine. DO THIS CAREFULLY AS THE ENGINE WILL CRANK OVER IF ALL IS GOOD. STAY CLEAR OF ANY MOVING PARTS AND HAVE HELPER ON BRAKES AND PARKING BRAKE SET.

Hope this helps.

BTW this is strictly for a starter that DOES NOT crank the engine and not for one that does crank the engine but does not start. That is another issue.






The CPS is a Hall effect transducer that varies its output voltage in response to changes to magnetic field. Inside the sensor there is a little magnet that lies along a piece of wire.
When the magnetic field is disturbed by the passing of the reluctor ring teeth it generates an inductive current in the piece of wire attached to the magnet.
The signal produced by the CPS is an analogic square waveform that varies in frequency in response to the overcoming speed (RPM) of the reluctor ring teeth and grooves. This tells the ECU at what speed the crankshaft is turning.
Another information provided by the CPS is piston top dead center (TDC). On the flywheel there are three big holes that produce a long "zero" signal. The holes are only three because in a six cylinder the pistons move in pairs, therefore you have two pistons at TDC at a time. Now, how does the ECU know which of the two TDC is fireing and which is exhausting?
That's the work of the sync pulse stator (camshaft position sensor) in the distributor. According to the position of the rotor the sync pulse stator recognizes which of the two is fireing and tells the ECU "hey, give fuel to cylinder number X!" and magically the engine turns over and runs all by itself...
------------------------------------------------------------------------------------------------------------------------
Front Axle Vac Disconnect

A short answer is Yes, the front axle always turns. It's just freewheeling when the T-Case is In 2WD or neutral.

Longer answer. If that Vac. disconnect on the right axle is disengaged , of course the right can spin independent of anything. Now, because the differential splits/balances the energy, the left is also effectively free as the stub, (inner axle) on the right can now spin.

Likewise, if the front drive-shaft is engaged for 4WD, you will still be in 2WD as that same right inner axle can just spin.

So when you select 4WD two things happen, (first). You just manually shifted gears in the TC to drive the front axle, AND triggered a vacuum switch to apply vacuum to that deal in the axle, the Vacuum disconnect. (or "Disco"). That has a deal so when the fork has actually moved over, engaging the splines, it opens a port letting vacuum back out to a switch that light's a light on the dash that says, "hooray!, you actually made it!"

They canned that disco a few years later, (96?). It's not necessary. There is I great little wright-up here somewhere where you can simply pull a clip, slide to fork over to engage, stick the clip back on the other side, then stick a fork in it, it's done. You will never loose 4WD because of that thing again.

BTW, one time my fork broke off. The base would still move over and light the light though.
************************************************** **************************
Try again - the AW4 is a 30-40LE with an extra clutch, built by Toyota, designed by Toyota, as used in the Celica, Supra, pickup, RWD van, and some RWD Lexus.

Just as the axles are shipped from Dana, the transmissions are shipped from Toyota - and the Toyota spec applies.

The BA-10 shipped from Peugeot, the AX-4, AX-5, and AX-15 all ship from Toyota (they're derivations of Toyota designs with different monikers - I believe the AX-15 is essentially a Toyota R150 light truck transmission.)

The early T4/T5 transmission (1984-1986 4-150 and V6-173) shipped from BorgWarner, and BorgWarner specs would apply in those cases (fortunately, they're just GL-3 gear oil to protect the bronze synchroniser rings, as in the AX-4/5/15. The BA-10 doesn't have a speck of yellow metal in it, which is why it can use GL-5. I know the FSM sez to use GL-5 in the AX-15 et al - this is one of those very limited cases where the FSM is itself wrong.)

I've heard of a TSB that sez the ATF +4 "Multi-Spec" can be used in the AW4, but reports from the field are mixed at best. Ergo, since Dexron is still available, use Dexron and save yourself the headache.

(TANGENT: Reports from the field on "power-flushing" the AW4 by forcing fresh fluid through it are mixed, but generally negative. If you suspect it's crudded up, the best method found to date is to buy a case of Dexron and 3-4 cans of B-12 "Chemtool" - dump in a can of Chemtool and change the fluid - hot! - in 1,000 miles. Repeat twice. This seems to be easier on the transmission and clutches than powerflushing.)

But, considering nearly every AW4 slushbox I've seen has had "Aisin Seiki" ID plates on it, I feel secure in saying it's a Toyota design as used...



ASD RELAY, PCU OPERATION

FUEL SYSTEM
FUEL DELIVERY
Automatic Shutdown Relay
The Automatic Shutdown (ASD) relay is located in power
distribution center near the battery or next to radiator coolant
recovery bottle.
The ASD relay is used by the PCM to supply voltage to fuel
pump, fuel injectors and ignition coil. The relay contacts are
normally open.
Power is supplied to relay coil when the ignition switch is
turned on. The PCM controls the ground circuit, which energizes the
coil and closes the relay contacts.
The PCM will only ground the relay when ignition switch is in
the RUN or START positions and activity is sensed through the
crankshaft position sensor and the camshaft position sensor in the
distributor. If the PCM senses the RPM signal has stopped, it will
remove the ground from relay coil, which will cause the contacts to
open and remove power from the circuit.
Ballast Resistor (Cherokee)
A ballast resistor, located between fuel pump relay and the
fuel pump, is used to reduce voltage to the fuel pump. This reduces
fuel pump noise during operation. Ballast resistor is mounted on
fender panel, next to washer fluid reservoir.
When fuel pump relay is energized, voltage is supplied to
fuel pump through the ballast resistor. During start and wide open
throttle conditions, ballast resistor is by-passed and fuel pump
receives its voltage from ballast resistor by-pass relay.
NOTE: Wrangler DOES NOT use a ballast resistor or ballast resistor
by-pass relay in the fuel pump circuit. The PCM operates
fuel pump through the fuel pump relay during all operating
conditions.
Ballast Resistor By-Pass Relay (Cherokee)
A ballast resistor by-pass relay is located on a bracket next
to power distribution center (next to coolant recovery bottle). By
switching the ground circuit on or off, the PCM can control fuel pump
(power) feed. The ballast resistor by-pass relay receives its voltage
from fuel pump relay.
Normally, voltage is supplied to fuel pump through a ballast resistor. At wide open throttle, fuel pump receives voltage through
the ballast resistor by-pass relay, which speeds up fuel pump to
compensate for higher fuel demand.
Fuel Pump (Electric)
All models are equipped with a gear/rotor type electric pump.
Pump is driven by a permanent magnet, 12-volt electric motor. The intank
pump is an integral part of the fuel gauge sending unit.
Fuel system pressure is maintained at about 31 psi (2.2
kg/cm�� ) when pump is operating and vacuum is applied to fuel pressure
regulator. With no vacuum applied to fuel pressure regulator, fuel
pressure should be 39-41 psi (2.7-2.9 kg/cm �� ) or higher. When fuel
pump is not operating, fuel pressure is maintained at 19-39 psi (1.3-
2.7 kg/cm�� ) by fuel pump outlet check valve and the fuel pressure
regulator.
Fuel Pump Relay
On Cherokee, fuel pump relay is located in the power
distribution center, next to coolant recovery bottle. On Wrangler and
Grand Cherokee, the fuel pump relay is located in the power
distribution center next to battery.
The feed side of the relay coil is powered by the ignition
switch. The relay is energized by the PCM by grounding the other side
of the relay coil. The relay contacts are normally open and will close
when the PCM provides a ground path for the relay coil.
The fuel pump circuit is completed during cranking and
whenever the engine is running. If the ignition switch is turned to
the RUN position, the fuel pump will operate for 1-3 seconds and then
shut off. If the PCM does not receive a crank or run signal, it
deactivates the fuel pump by opening the relay coil ground circuit.
The 1-3 second time limit is used to prevent unnecessary operation of
the fuel pump once the system is pressurized. If the engine were
running, the PCM would maintain the fuel pump relay coil ground
allowing continuous operation of the fuel pump.
FUEL CONTROL
Fuel Injectors
The fuel injectors are controlled electronically by the PCM.
Because each injector is connected to 12 volts, the injector is
energized when connected to ground through the PCM. The PCM also
controls the amount of time the injector is energized (pulse width).
Pulse width is based on various inputs and is calculated by the PCM.
The fuel injectors are sequentially energized (in firing order) by the
PCM.
With injector connected to a pressurized fuel supply, a fine
mist will spray from the injector nozzle into the intake manifold. The
injector uses an electromagnet and spring pressure to open or close
the fuel metering plunger. When connected to battery voltage, the coil
of wire in the injector becomes an electromagnet. The magnetic field
generated will overcome spring pressure and raise the plunger off its
seat. When the injector circuit is opened by the PCM, the magnetic
field collapses and spring pressure forces the plunger against its
seat.
Whenever an injector is opened, it will always spray a
consistent amount of fuel for a given amount of pressure. Because
pressure drop across the injector is fixed and the fuel flow rate
constant, the only control variable is the amount of time injector is
open. By controlling the time the injector is open (pulse width), the
PCM can decrease pulse width for engine idle or it can increase pulse
width at wide open throttle.
Injection Timing
All engines use a sequential port fuel injection system. This
means that the injectors have a specific firing order and fuel
injection is timed to piston movement. The spark plugs and injectors
are fired in the same order: 1-3-4-2 on 2.5L and 1-5-3-6-2-4 on 4.0L.
In order for the PCM to fire the injectors in a specific
order timed to crankshaft and piston movement, it has to establish a
reference point. Establishing the reference point requires PCM inputs
from the crankshaft position sensor and camshaft position sensor.
The crankshaft position sensor is located on transmission
bellhousing and provides the PCM with crankshaft angle and speed. The
PCM converts crankshaft speed into engine RPM and crankshaft angle
into piston position.
On 2.5L engine, the slotted flywheel/drive plate, rotating
past the sensor, contains 2 groups of 4 slots located 180 degrees
apart. Each group of slots represents the position of 2 of the
pistons. Pistons No. 1 and 4 approach TDC at the same time and use the
same flywheel slot, while piston No. 3 is matched with piston No. 2.
On 4.0L engine, the slotted flywheel/drive plate, rotating
past the sensor, contains 3 groups of 4 slots located 120 degrees
apart. Each group of slots represents the position of 2 of the
pistons. Pistons No. 1 and 6 approach TDC at the same time and use the
same flywheel slot. Pistons No. 2 and 5 are matched, while piston No.
3 is matched with piston No. 4.
The PCM, through the crankshaft position sensor, knows that 2
pistons are approaching TDC and uses the sync signal generator on the
camshaft position sensor to determine which injector/spark plug to
fire.

************************************************** ***************************
IAC CLEANING 88

The Idle Air Control (IAC) is mounted on the back of the throttle body. The valve controls the idle speed of the engine by controlling the amount of air flowing through the air control passage. It consists of a stepper motor that moves a pintle shaped plunger in and out of the air control passage. When the valve plunger is moved in, the air control passage flows more air which raises the idle speed. When the valve plunger is moved out, the air control passage flows less air which lowers the idle speed. Over time and miles, the IAC can get carboned up which can have an adverse affect on idle quality. Cleaning the IAC may restore proper function and is an easy procedure to perform and good preventive maintenance so it is never a bad idea.

CLEANING THE JEEP 4.0 IDLE AIR CONTROL

Remove the air filter cover, associated hoses and the rubber boot that goes from the air filter cover to the throttle body. Remove the IAC with a torx driver (2 bolts; one can be kind of hard to get to)

“Gently” wiggle out the IAC from the throttle body. Gasket on the IAC can be re-used if it is not damaged

Clean the IAC with a spray can of throttle body cleaner; inexpensive and available at any place that sells auto parts. Throttle body cleaner is recommended rather than carburetor cleaner as it is less harsh, safe for throttle body coatings and is best for this task. Use cleaner, a rag and a toothbrush and or Q-Tips. Be gentle; don’t twist or pull on the pintle that protrudes from the IAC as it is fragile and you could damage it.

Thoroughly spray clean and flush where the IAC seats in the throttle body with the same spray cleaner

It is also a good idea to clean the entire throttle body itself, the butterfly valve inside of the throttle body and all associated linkage as long as you have things disassembled

Reinstall IAC and check idle quality.


COIL RESISTANCE, mine. Meter on the 20K scale reads 6.4 between the secondary and the first yellow positive. Secondary to ground reads nearly 20 on the same scale.
************************************************** ***********
Track bar/panhard rod. 1 nipple at chassis end
* Track rod ends. 1 at each end of axle and 1 at the steering box drop arm. Possibly 1 at the mid-joint of the drag link but I think this one is usualy not greasable? so 3, maybe 4 on the steering linkage.
* Steering swivel ball joints. The top ball joint is greasable and this is easier to get to if you take the wheels off but not essential. The bottom ball joint isn't usually greasable but I think some specialist aftermarket ones might be.
*Front axle driveshafts have a UJ at each axle end. These are often not greasable but they can be and the grease fitting may be the usual nipple between 2 of the bearing caps(although there is no room to get a conventional grease gun in to it) or a flush fitting on the end of 1 of the bearing caps.
*Front propshaft has a greasable sliding joint and 3 UJ's which probably won't be greasable if they are original. The UJ nearest the gearbox could be greasable by the bearing end cap as there is no space to get to an inner grease nipple.
* Rear propshaft has 2 UJ's which again probably aren't greasable but worth checking. The sliding joint of the rear propshaft has to be dismantled to grease it but it is advisable to do it every few years, undo the uj straps at the rear axle(4x 8mm headed bolts) and remove the prop to grease the splines.


MMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMMM
Just in case you are looking for something to do;
That rear manifold bolt has a habit of loosening. On anything like that you NEVER want to tighten only one. It can warp/bend, even crack things. If I found that any that where easy to reach where loose, I'd pull the air cleaner and tighten them all, starting in the middle and working out towards the ends. I'd go over three times, a tad tighter each time. It's a bear of a spot to get a torque wrench on them all. Just don't ape on it. If its firm and not turning, no point in going on to break it, a REAL *****. The rearmost bolt underneath takes a little doing, but it can be done with the right extension(s?). For that very back one by the firewall I use way long extensions (18"), with a swivel at the socket. The E-fan comes out in a snap with only the two little top cap screws, I forget if that helps or not. Anyway, that's a good thing to check on any old Jeep.
(Check your motor mount while the air cleaner is off)

 

FlinStone thanks for all the information. I would like to make sure its solid before i start modding. You gave me plenty of informatrion to read up on.

 

Course I can't swear every word is accurate. Funny you chose the word "solid". Some 1000's of trips on my road have mine crumbling. Parked torqued the other day my hatch hit the tail light. Cracks everywhere, and 300K coming up. Not sure what I'm gonna do with that.

I noticed the same type of cracks on my 84 as well. I guess if it's been on pavement you should be better off with that.

 

After picking up a 1990 Laredo - check and clean the 'dip stick' main ground...fixed many bugs. That and the coolant tank.

Just had the radiator crack so I am about to change that out...

 

Check/change all fluids & filters, check bushings and steering joints, ect. just as any other car you buy. Then go on to performing Cruiser's tips for the Renix specific stuff. If it has ABS read about the Bendix 9 system and decide if you want to eliminate it like I and many of us have. If it has a Dana 35 rear end and you plan to wheel it hard with big tires you'll want to replace it with something else. If it has ABS it has a D35 for sure, if no ABS then maybe. I think the '98 had stronger front axles, but the early ones are fine if you're not punishing it.

 

Yup.

Renix Ground Refreshing

The Renix era XJs and MJs were built with an under-engineered grounding system for the engine/transmission electronics. One problem in particular involves the multiple ground connection at the engine dipstick tube stud. A poor ground here can cause a multitude of driveabililty issues, wasted time, failed emission tests, and wasted money replacing components unnecessarily.

The components grounding at the dipstick tube stud are:

Distributor Sync Sensor, TCU main ground, TCU “Shift Point Logic”, Ignition control Module, Injectors, ECU main ground which other engine sensors ground through, Oxygen sensor, Knock Sensor, Cruise Control, and Transmission Sync signal. All extremely important stuff.

The factory was aware of the issues with this ground point and addressed it by suggesting the following:

Remove the nut holding the wire terminals to the stud. Verify that the stud is indeed tightened securely into the block. Scrape any and all paint from the stud’s mounting surface where the wires will attach. Must be clean, shiny and free of any oil, grease, or paint.

Inspect the wire terminals. Check to see that none of the terminals are crimped over wire insulation instead of bare wire. Be sure the crimps are tight. It wouldn’t hurt to re-crimp them just as a matter of course. Sand and polish the wire terminals until clean and shiny on both sides. Reinstall all the wires to the stud and tighten the nut down securely.

While you’re in that general area, locate the battery negative cable which is fastened to the engine block just forward of the dipstick stud. Remove the bolt, scrape the block to bare metal, clean and polish the cable terminal, and reattach securely.

Another area where the grounding system on Renix era Jeeps was lacking is the engine to chassis ground. There is a braided cable from the back of the cylinder head that also attaches to the driver’s side of the firewall. This cable is undersized for it’s intended use and subject to corrosion and poor connections at each end.

First off, remove the cable end from the firewall using a 15mm wrench or socket. Scrape the paint off down to bare metal and clean the wire terminal. Reattach securely.
Remove the other end of the cable from the rear of the head using a 3’4” socket. Clean all the oil, paint and crud from the stud. Clean the wire terminal of the cable and reattach securely.

A suggestion regarding the braided cable:
I prefer to add a #4 Gauge cable from the firewall to a bolt on the rear of the intake manifold, either to a heat shield bolt or fuel rail bolt. A cable about 18” long with a 3/8” lug on each end works great and you can get one at any parts store already made up. Napa has them as part number 781116.

A further improvement to the grounding system can be made using a #4 cable, about 10” long with 3/8” terminals at each end. Attach one end of this cable to the negative battery bolt and the other end under the closest 10mm headed bolt on the radiator support just forward of the battery. Napa part number 781115.

For those of us with Comanches, it’s very important to remove the driver’s side taillamp assembly to access the ground for the fuel pump. Remove the screw holding the black ground wire. Scrape the paint from the body and corrosion from the wire terminal. Reattach securely.

If you want to upgrade your grounds and battery cables in general, contact Jon at www.kelleyswip.com. He makes an incredible cable upgrade for a very reasonable price.


Revised 03-04-2013