Polluting...Like a BOSS
05-02-2012, 03:16 PM
#46
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Year: 1987
Model: Cherokee
Engine: I6
Gassy oil is relatively normal when u get up in miles. Rings just aren't as resilient as they used to be. Did you test all your sensors yet? Could be as simple as the temp sensor not reading right keeping it in open loop. Start small man. Get your basics covered before you go tearing through it. You have oil pressure right? Glittery stuff like that can happen when bearings get way way way worn but at that point it should start sounding like a diesel if everythings is wearing fairly evenly. I have helped a coupler people with cherokees around here pass smog. On our lovely renix one sensor will easily cause it and you have no cel.
I did get around to checking sensors today at lunch. Everything checked out fine so I was stumped. THEN I decided to check the knock sensor and it fell apart in my hand when I went to unplug it. I gave it a quick test drive and WOW I can brake the tires loose now.
I think it failed and caused my timing to be retarded. Yesterday I went through a pass and I had to cruise in 2nd to maintain 50mph. I bet today it will make it no problem.
I'm still going through with more thorough testing on all systems. Right now I have confirmed a manifold leak so I will have to repair that. CTS and MAT are reading normal. Thermostat is ordered because it takes quite a bit of labor to get up to operating temp then it cools back down to 160* when I'm cruising. I need to replace my starter cause I am tired of smacking it with a hammer every time I want to start the Jeep. Just added to the list of parts needed is a knock sensor.
Overall I think I have made some progress. I will update as I go.
05-02-2012, 03:53 PM
#47
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Year: 1990
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Knock sensor generates a signal to retard timing. If it is destroyed, it should make no signal and therefore not have been causing retarded timing.
I ran into this the other day. Had the DRB hooked up to my buddy's 88 Xj that was intermittently running rich. Keep in mind that the DRB sees what the ECU sees. It's not the same as testing a sensor at it's connector. What we found was CTS reading was low, and changed when the C101 connector was wiggled. I'd be refreshing the C101 as a matter of course.
I ran into this the other day. Had the DRB hooked up to my buddy's 88 Xj that was intermittently running rich. Keep in mind that the DRB sees what the ECU sees. It's not the same as testing a sensor at it's connector. What we found was CTS reading was low, and changed when the C101 connector was wiggled. I'd be refreshing the C101 as a matter of course.
05-02-2012, 04:34 PM
#48
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Year: 1987
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Knock sensor generates a signal to retard timing. If it is destroyed, it should make no signal and therefore not have been causing retarded timing.
I ran into this the other day. Had the DRB hooked up to my buddy's 88 Xj that was intermittently running rich. Keep in mind that the DRB sees what the ECU sees. It's not the same as testing a sensor at it's connector. What we found was CTS reading was low, and changed when the C101 connector was wiggled. I'd be refreshing the C101 as a matter of course.
I ran into this the other day. Had the DRB hooked up to my buddy's 88 Xj that was intermittently running rich. Keep in mind that the DRB sees what the ECU sees. It's not the same as testing a sensor at it's connector. What we found was CTS reading was low, and changed when the C101 connector was wiggled. I'd be refreshing the C101 as a matter of course.
I did find a few posts on other threads where the knock sensor had failed causing a short which in turn retarded the timing. Mine is now hanging on the side of the block with nothing connected = no retarded timing.
Does that sound right? I don't know what else would explain my former lack of power that is now gone when the only thing changed is the knock sensor.
05-02-2012, 05:14 PM
#49
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Year: 1990
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Let's see what develops.
At idle, wiggle your engine harness near the C101, the MAP, and along the valve cover. See if the idle changes. Did you ever check your sensor ground circuit itself?
Cruiser’s Renix Sensor Ground Test
Set your meter to measure Ohms. Be sure the key is in the OFF position. 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. Wiggle the wiring harness where it runs parallel to the valve cover and also near the MAP sensor mounted on the firewall. If you have an 87 or 88 with the C101 connector mounted on the firewall above the brake booster, wiggle it, too.
Revised 04/09/2012
At idle, wiggle your engine harness near the C101, the MAP, and along the valve cover. See if the idle changes. Did you ever check your sensor ground circuit itself?
Cruiser’s Renix Sensor Ground Test
Set your meter to measure Ohms. Be sure the key is in the OFF position. 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. Wiggle the wiring harness where it runs parallel to the valve cover and also near the MAP sensor mounted on the firewall. If you have an 87 or 88 with the C101 connector mounted on the firewall above the brake booster, wiggle it, too.
Revised 04/09/2012
05-02-2012, 05:35 PM
#52
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That's why I put the dates on them so you can keep track!! I changed this one to include wiggling the harnesses. I'd like to find a good reliable place to keep all my write-ups posted and current. Been talking with Scott from www.jeepseekers.com about doing just that.
05-02-2012, 08:41 PM
#54
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Is anyone else having trouble here? I get;
Server not found.....Firefox can't find the server at www.jeepseekers.com.
Worked a couple days ago.....
Server not found.....Firefox can't find the server at www.jeepseekers.com.
Worked a couple days ago.....
05-02-2012, 09:44 PM
#55
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Year: 1990
Model: Cherokee (XJ)
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Is anyone else having trouble here? I get;
Server not found.....Firefox can't find the server at www.jeepseekers.com.
Worked a couple days ago.....
Server not found.....Firefox can't find the server at www.jeepseekers.com.
Worked a couple days ago.....
05-03-2012, 07:59 PM
#56
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Year: 1987
Model: Cherokee
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Let's see what develops.
At idle, wiggle your engine harness near the C101, the MAP, and along the valve cover. See if the idle changes. Did you ever check your sensor ground circuit itself?
Cruiser’s Renix Sensor Ground Test
Set your meter to measure Ohms. Be sure the key is in the OFF position. 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. Wiggle the wiring harness where it runs parallel to the valve cover and also near the MAP sensor mounted on the firewall. If you have an 87 or 88 with the C101 connector mounted on the firewall above the brake booster, wiggle it, too.
Revised 04/09/2012
At idle, wiggle your engine harness near the C101, the MAP, and along the valve cover. See if the idle changes. Did you ever check your sensor ground circuit itself?
Cruiser’s Renix Sensor Ground Test
Set your meter to measure Ohms. Be sure the key is in the OFF position. 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. Wiggle the wiring harness where it runs parallel to the valve cover and also near the MAP sensor mounted on the firewall. If you have an 87 or 88 with the C101 connector mounted on the firewall above the brake booster, wiggle it, too.
Revised 04/09/2012
Now it either idles really low when I start it or it goes to 1K and sits there.
05-03-2012, 08:37 PM
#57
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[QUOTE=JeepDeep;1745989]No change in idle. However, I did Ohm terminal be to neg battery terminal and it was a rediculous number. I started ripping off the rotted cable wrap and following the wire to C101 and right before I got there it went into a brass crimp that added two more wires to the circuit. On one side I had 0 ohms and the other side I had 27! So I brushed a bunch of flux on the connection and covered it with solder. Now I can poke ground wherever I want in the engine bay and have .2 or better ohms to terminal B on the TPS.
Good job. I've seen that many times.
Now set your TPS again since it will have a good ground.
Good job. I've seen that many times.
Now set your TPS again since it will have a good ground.
05-03-2012, 08:38 PM
#58
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There's an intake air control thing on the TB. I haven't done mine, but you can remove it and gently clean it. I found this somewhere....
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.
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.
05-03-2012, 08:48 PM
#60
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Year: 1990
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