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Techyon
August 4th, 2007, 18:36
Ok,

Its got the 4.0 liter, 110 k miles,
Now the problem has become its stalls everytime it starts to idle.
Its not everytime its completely intermitant.
So say I'm driving down the road doing 35, let off the gas and start to coast, it sometimes stalls, and also at red lights, No warnings no spits sputters just dies.

Ok it will restart "when its ready" today it did it 5 times on a 28 mile trip, longest time I had to wait was 10 minutes, during that time I tried to test for spark. I had NONE.

45 seconds later.. it started up and made it 4 miles home.

Ok, I've replaced within the last 4 months the
TPS - Throttle position sensor
IAC - Idle Air Control
ICM - Ignition Control Module
Coil
Crankshaft position sensor
Cap, rotor, plugs and wires

So anyone who can be of some help would be GREATLY appreciatted.
I'm baffled now, I had someone help me on here before when I had bathed the engine bay and drowned the ICM, I replaced it then with a working junkyard pull. As well as the TPS.
SO its been since then it ran "ok" this month Ive bought everything again with the exception of the Crankshaft position sensor, that was also last summer when trying to find why I had lost spark due to water.

Its a renix jeep, so is there any way to get a scan tool to talk to this jeep?

Thanks,
Techyon

cumorglas
August 4th, 2007, 19:06
I bring this up because it is renix and it's common. check all your grounds. clean them till they shine. put them back tight with some appropriate goo(i use a a teflon based goo from marine applications, i know others that swear by ox-guard, i am sure there are others.) every renix jeep can benefit from this. i also recommend replacing the stupid little flat braid with something beefy. i used 0 welding cable because it was laying around.


all that done. what you describe sounds like CPS issues. it may not be the cps itself that is bad. it could be the connector or a wire has been weakened and gets wierd under heat and motion. funny, the stock ones sometimes last decades but the replacement only a year. the first time i had cps issues it took me a long time to figure it out because i hadn't yet heard of naxja, and didn't yet have the renix manual.

Techyon
August 5th, 2007, 00:55
Ok, thanks for that tip, I've got some 2 Guage wire laying around from a job I did. I'll be trying that in the morning.

As for the CPS I'm guessing you mean the ECM or Ignition Control Computer?

SuperRA
August 5th, 2007, 01:12
Ok, thanks for that tip, I've got some 2 Guage wire laying around from a job I did. I'll be trying that in the morning.

As for the CPS I'm guessing you mean the ECM or Ignition Control Computer?

CPS = Crankshaft Position Sensor

Ecomike
August 5th, 2007, 10:39
X2 on the grounds!

Best Renix scan tool ever made was and still is a multi meter, best to have an analog (old style needle display) multi meter for certain tests. All renix sensors can be tested with an analog Mmeter. So can all the ground wires.

Loose wire on the connectors in the igntion switch could also be casuing your problems. The ignitions switches (not the key lock mechanism) are week and inadequite and are overloaded current wise. I finally bypased the igntion switch on several loads that were causing the problem, namely the AC blower, turn signal, radio and power windows that all use a 14 (or 12) gauge piss-ant wire they run throught the ignition switch to run all those loads. I ran a new 10 gauge wire and dash panel, 30 amp fused, switch for them and left the rest on the new ignition switch.

You also have the C-101 bulkhead connector in the 87 model, just above the brake booster which has caused lost signals for many others (mine is still working, knock on wood). All the ECU sensor signals and ECU to injector signals pass though the C-101 connector. One loose connector in it can cause your troubles.

Leave the sensors and CPS alone for now. Do the grounds, ignition switch and check the C-101 connector for signal or ground losses when wiggling the wires, harness connectors and C-101 everywhere.



I bring this up because it is renix and it's common. check all your grounds. clean them till they shine. put them back tight with some appropriate goo(i use a a teflon based goo from marine applications, i know others that swear by ox-guard, i am sure there are others.) every renix jeep can benefit from this. i also recommend replacing the stupid little flat braid with something beefy. i used 0 welding cable because it was laying around.


all that done. what you describe sounds like CPS issues. it may not be the cps itself that is bad. it could be the connector or a wire has been weakened and gets wierd under heat and motion. funny, the stock ones sometimes last decades but the replacement only a year. the first time i had cps issues it took me a long time to figure it out because i hadn't yet heard of naxja, and didn't yet have the renix manual.

Ted Young
August 5th, 2007, 10:42
We had a problem just like this on a '94 Bronco. It was the distributor trigger (the wire harness/sensor located in the distributor with the magnetic pickup).

I know these are different beasts, but just thought I'd throw it out there.

Ecomike
August 5th, 2007, 11:05
Renix can run without the distributor pick up connected. Don't know if an intermitent distributor pickup would confuse it enough to kill the engine, but I doubt it.

We had a problem just like this on a '94 Bronco. It was the distributor trigger (the wire harness/sensor located in the distributor with the magnetic pickup).

I know these are different beasts, but just thought I'd throw it out there.

bpatrick54
August 6th, 2007, 21:13
I just had a similar problem with my 88 cherokee. Like yours it has the 4.0 and a couple of weeks ago it started with the same random stall problem. I finally tracked it down to a disconnected vacuum line on mine. there is a group of small vacuum lines that run alongside the air cleaner then thru a plastic bracket. One of these had fallen off and was causing everthing from the stall problem, to a rough idle, to high idle problems.

I also have the no restart when hot problem you have, and this has not fixed that. "Hope that this helps

cumorglas
August 6th, 2007, 21:30
All the ECU sensor signals and ECU to injector signals pass though the C-101 connector. One loose connector in it can cause your troubles.

Leave the sensors and CPS alone for now. Do the grounds, ignition switch and check the C-101 connector for signal or ground losses when wiggling the wires, harness connectors and C-101 everywhere.

i forgot about the c101. they are evil. if ecomike lived in a place where you spray saltwater into your engine compartment five months a year he would understand the true depth of their perfidy. his advice, however, is solid. even if at least one of his xj's has no ignition at all.

Techyon
August 10th, 2007, 12:29
I cant beleive I missed something so simple, Today I started to trace wires, I was looking at the C101 connector when I noticed something wrong, the new CPS I installed last fall's wire had moved around and found the exhaust manifold.
The wires are both cooked bare in a spot about an inch long.
I now am heading over to a friends garage to try to get help pulling the CPS out so I can re-splice the wires, I cant find a way to reach them from topside and its been raining here for two days..

Thanks for All of the help sofar guys,
Now Im sitting here wondering if its just worth taking the ICM and coil back to the store and getting 170.00 dollars back. :o

I saved the old ICM and coil just in case something like this would happen.
Just lost the box for the ICM to the garbage.

8Mud
August 10th, 2007, 18:33
I cable tied my CPS wires to my speedo cable, there is usually a bunch of extra wire for the CPS leads anyway. I just left enough slack, so the engine can move around some without stressing the wires. The wires run well away from the manifold this way.
Funny when I replaced the stock CPS, there was a coil of extra wire just sitting on top of the bell housing with nothing holding it in place. I guess it had been sitting there for 200,000 miles or more.

SuperRA
August 10th, 2007, 18:43
Now Im sitting here wondering if its just worth taking the ICM and coil back to the store and getting 170.00 dollars back. :o

I saved the old ICM and coil just in case something like this would happen.
Just lost the box for the ICM to the garbage.

I'd be VERY surprised if any auto parts store took back an electrical part, esp. without a box! Good luck ;)