vistacruiser

Also, Fantic ... think they had busted something off the distributor they call 'dog ears' ... so the dist. can be twisted some. Does that sound right?. The shim Dan is referring to on the CPS would just move it in and out or more in line with ... not closer or farther away from the fly, or so it appears, according to the drawing I posted earlier. Probably only takes a few micro-volts to trigger the computer though, right?

fantic238

The Renix (renault-bendix) injection system is very well engineered.
Conceived when emission controls were not so rigid, with the only purpose to work in every condition.
The contol unit has both open-loop and closed-loop operation mode.
The good thing about it is that it continues to work with faulty sensors (except CPS and MAP)
If you unplug the O2 sensor, knock sensor, MAT sensor and fluid temp sensor, it will use preloaded default settings to keep the engine running in open loop mode. It also calculates an estimation of the MAT sensor readings crossing the informations from the MAP and the fluid temp sensor.
European models from '87 to '90 even came without cat and O2 sensor (only open loop mode). You have the O2 heater relay (working) and harness connector where the O2 sensor is supposed to be but there is just a cap on the exhaust instead.
So all this debate weather the O2 sensor is good or not is useless. On a renix system the O2 sensor is basically USELESS.
Different story with the OBD I&II. People are forced to fix the faulty sensors to avoid circulation in open loop mode and produce a little more pollution.
That's what it's all about, emissions.
Functionality is something different.

Getting back to the issue,
after I have personally burnt 4 stock FP (Bosch 0 580 810 019), a couple for running out of gas, and another couple for extreme offroading angles, i decided to upgrade to a heavy duty external, auto-fishing FP (Bosch 0 580 464 070). This pump sucks and pushes fuel, air, air+fuel, mud, rust etc. at 3bar and 130 liters/hour. The difference is in the shape of the impeller that provides the volumetric action with small rotating cylinders instead of the traditional gears that have very little tolerances.
It is noisy, but it never stops pumping.
After replacing my pumps i noticed that if i didin't bleed the fuel line correctly it would run like ****t.
A bad pump will work fine for the first 2 or 3 minutes until it gets hot and the gears seize in the housing. The consequent reduction in flow (not pressure, that stays the same, we are talking of volumetric pumps, exactly like an oil pump) won't be able to feed the fuel request.
(Note: the injectors spray all together in crank mode and open twice per active cycle in warm-up mode)
Jumpering the ballast resistor may be something to try too.
But before investigating on the fuel system, like i said, i would check the EGR operation and the EGR pipe correct installation.

'87-'89 models are the same, '90 models have the newer type connectors, '91 onwards are chrysler.

vistacruiser

Excellent write up, Fan ... love it ... an eye opener for me. Very very informative to me .... Answered my question about pressure and running out of fuel very well ... I see that it can have a bad pump and plenty-o-pressure now.

What about this 'dog ears' on the distributor thing? Clue me in a bit more on this, please, sir

mike37

you are not suppose to adjust the timing cus its controlled by the ecm
the dogs keep it set at the right position


technically turning the distributor is not adjusting the timing
the cps is doing that

the ecm is getting signals from two sensors to determine when to spark and give fuel

the one in the distributor and the cps on the crank
if the dist is set to far out of rang the ecm wont be able to compensate

so after karen7 gets a new HB she needs to reset every thing and set the DIS to the stock position

fantic238

You mean drilling the distributor cap holes oval?
It's basically the same as the CPS drilling story.
The main difference is that the dist. drilling affects ignition timing adjustment much less than the CPS relocation.
The CPS is a Hall effect transducer (like the pick-up of a stratocaster) with the magnet in the sensor. When the little windows and tabs of the phonic rotor on the flywheel pass in proximity of the sensor the magnetic field of the little magnet changes and generates an induced current flow in the piece of wire it is attached to.
It produces a square wave signal (on-off) that tells the ECU when to trigger the ignition coil and provides informations on the angular velocity of the crankshaft (RPM).
The cool part is that if you move the CPS you can offset the square wave peaks and anicipate/retard the triggering of the ignition coil without affecting the RPM readings.
I have done this on my CPS to anticipate since i'm running propane but i don't like it because it is not easily reversible and when i switch back to gas it's too anticipated and the knock sensor doesn't work it out that much.

vistacruiser

Right on Mike37 ... I was wonderin' at one point just about how much mechanical timing error the ecm could compensate for. That clears that up for me. Also the 'dog ears' thing too ... I was kinda' thinkin' it was something like that but not sure. Now I get it.

Well ... I have a couple of them ..... one with Texas Specials and the other with Lace Sensors ... lol. Good to know in case another CPS fails on the road and I'm carryin' one of my axes ... could rig it to run and get me out of a jam, maybe. ... Kiddin' aside, Fan ... you are a very astute tuner. I am virtually clueless in that regard. Really enjoy reading your stuff.

Mark Knopfler wrote "Sometimes you're the windshield, some times you're the bug" ... well, today, I'm the sponge. Wonderful, informative stuff, guys ... thank you. Love it.

karen7

How do you test for volume? I would hate to spend $80 on another part that I don't need and can't take back and it not fix the problem. But I do understand how you can have pressure but no volume, took me awhile to get it but I do.
(I'm tapping into my vacation money now)
How do i do this? I know originally once the motor was in they couldn't get it started. I was looking around and found these 2 plugs not plugged in, turns out it was the ballast plugs. Plugged them in and it started.

Fan, you are very educated on this motor. Thank you. And also another big thanks to Vista and Mike and everyone else. You guys are the best group of jeep detectives anyone could have. I am so glad I found this forum and I know we will figure this out. Everyone else I know is telling me to sell it and take my loss that we got a bad motor. I have faith.

fantic238

Hi Karen, congrats for your knowledge and determination. I wish there were more Women like you here.
You can do a flow test by unplugging the fuel return hose from the sending unit at the tank and put it in a jerry can. Then jumper the fuel pump relay base between connector 87 and 30 with a thick piece of wire to run it continuously for exactly five minutes.
Measure the amount of fuel (in gallons) in the jerry can and if it's less than 2.8 gallons the fuel flow is insufficient. A good average for a used pump is between 2.6 and 3.
The ballast resistor lowers the voltage to the FP and the O2 sensor heater to reduce wear and noise after the engine has started.
Insert the "famous" two inch piece of wire (jumper) between the two connectors to keep the pump running at 12volts and spin faster.

You are welcome, just wanting to help.

vistacruiser

Ok, Karen ... I just did a search on Fuel pump test ... long list of results ... there is probably one there that is pertintent, but I'll take a stab .... maybe you could run that search and see what you dig up ... anyway ..

First be certain there is plenty of gas in the tank ... don't wanna' run it out again, right? then disconnect the fuel line at the fuel rail, or other convienient spot, and attach a suitable drain hose, something to keep from shooting gas all over the place, and run that hose into a clean, empty gas can of about 5 gallons volume. I THINK that should leave enough room for the test. Once you're sure you're not gonna cause a fire or environmental disaster, turn the key to ON ... fuel should then begin to pump. I'm sayin', and this is just my gut inclination, to leave it run for about three minutes and watch the flow from the end of the hose carefully, making sure it doesn't spill over the gas can. Either that thing will pump like mad and keep on pumpin' or it will slow, or go to a trickle or maybe even quit altogether. If it slows way down, trickles or quits you know we got an issue. Regardless there will be gas in the can ... and that is the 'volume' that was pumped. May tell us something there. Also you can put the gas back in the tank when you finished, right? That is my idea of a redneck f/p volume test.

Jumping the ballast resistor is as simple as putting a jumper lead across the two terminals of the ballast resistor where those two wires you mentioned earlier are connected. In other words, effectively connecting the aforementioned wires together.

vistacruiser

LOL ... fan ... you beat me ...

vistacruiser

And also described a much better test than I did .... right on !!

karen7

I did the volume test but I had to modify the time and amount by half because I needed a smaller jug and my hose was too short. So I did 2.5 mins and got approx 1.5 gals. It was a steady flow of gas the whole time.
I got the new HB but wasnt able to get it on yet cause it got dark and I need an installer. Also got injector O-ring kit.

After doing the volume test, I started it and it took the fuel a little better not good but still backfired.
Now once we took the balancer off I cranked it just to see what happened. It wouldn't stay running, but while I was cranking and kept the key as far on as possible, it seemed to sound ok. I kno its not good to crank on it very long, but I wanted to hear what was going on without the balancer. Sounds like it was so out of time it couldn't stay running.
Dist was set back to original position.

vistacruiser

good report, K ... your installers know not to beat that balancer on, right .. lube the crank snout and just tap in the center if it's stubborn., not around the edge, just a bit until the big bolt will start a few threads ... then torque the bolt and washer down and it'll snug the balancer right along with it. Sounds like the pump is OK to me ... maybe Fan has another idea ?... Mike is pretty certain that the balancer is at the root of this issue, since everything was set off of it initially ... the outer ring with the timing marks on it is held on only by bonded rubber, so when rubber bond fails and the outer ring slips, (and Mike says it is a known fault of this motor) the marks move and everything that has been set by that mark could be also subsequently wrong ... domino effect ... make any sense?... so keep the fingers crossed. This bone yard oughta be givin' you some compensation too ... running motor my foot .

karen7

Yup makes perfect sense. I said this exact thing from the beginning myself.

They do this time. The 1 off the old motor couldn't be reused cause they beat on it to get the motor out.

Would be nice but I can't say for sure that Chuck or my bro didn't ruin the balancer themselves.

I thought I mentioned this earlier but I guess not. The guys at work said the motor and jeep are junk and sendit for srap or sell it cause I won't get it running. Now I have to get it running, I told them I would and I'll be driving it into work soon to show them patience pays off and you don't have to kno how to fix a vehicle as you can read and ask the right questions.

fantic238

That was the result of the correct bleeding. FP flow test is ok.
You need to check timing with piston and valves positions. Don't trust the dots. Vista certainly knows how.