About to call it quits and part the damn thing out. Please help!!

I am sick and tired of working on my Jeep and not getting any results. I am about to just part it out and try to recoup some of my money. It's an '89 Cherokee 4.0l with a 5spd. Here's the story:

When I bought the Jeep it ran and drove, kind of. I had to replace the slave and master cylinder but it still ran. When that was done I drove it around for a bit without any issues. I got through most of a tank of gas when it started acting up. While at idle something would happen and I wouldn't be able to accelerate. It would just pop and spit and wouldn't go over about 1k rpms. I originally thought it was a clogged fuel filter because the jeep sat for a while before I bought it and sat some more while I worked on the tranny. I replaced the filter,put some more gas in it and drove it home fine. But then it happened again. Now I'm thinking there most be a bunch of crap in the tank so I replace the filter again and drive it home fine. And there it sat for a while. It seemed to only die after driving for a while in city traffic so it was always hot when it happened. There is no temp gauge on my cluster so I don't know if it was overheating or not. My plan was to use the Jeep for road trips so I decieded to go ahead and tear it down and do some major service on it and hopefully I would fix this other problem while I was at it. Here is what all I have done:

Had gas tank cleaned
New fuel pump
New fuel filter
New headgasket and all other gaskets
New distributer cap and rotor
New plugs and wires
New thermostat
All new hoses
New belt
New sensors: TPS, MAP, O2, Coolant switch and temp sensor
CPS checks out okay as well as MAT
Replaced coil with used one
Swapped out injectors with used ones
Fuel pressure checks out
Swapped out fuel pressure regulator with used one
Replaced ground wires
Compression checks out
Oil and filter change
New battery
Checked for and fixed any vaccum leaks
EGR does not seem to be stuck

The plug on the #3 cylinder has oil on the threads. A few others have some as well but it is very minimal.

I think that's about it. Now the problem is bad enough that it does it on a cold engine. It starts and idles just fine but won't rev over 1k rpms. Please help before I scrap the damn thing. Any help will be greatly appreciated.

thanks,
Brandon

have you tried changing out the ignition module with a known good one? If bad it gets real hot (to hot) and will shut the jeep down and limit the revs. Also check the condition of the pickup coil in your distributor.

Where is the ignition module? And I don't really have any experience with distributors so I don't know what the pickup coil is either.

The ignition module is mounted on the left infront of the shock tower. The ignition COIL sits above it, with a harness and a thick wire that goes to the distributor cap. Inside the cap, underneath the rotor you'll see the pickup module. This is very much similar to the Crank sensor in that it reads based on magnetism.

It's also called a Cam sensor and will not cause what your describing. It would cause low power and a delayed hot and cold start. It will run without it connected, but performance will suffer. So disconnect it and take for a drive and see if it still does it (it probably will, I doubt theres anything wrong with it)

beater_xj said:

Where is the ignition module? And I don't really have any experience with distributors so I don't know what the pickup coil is either.

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Get a re-man distributer, they are around $50 at Advance Auto.

Sounds like the distributor timing is off a tooth.

Check your converter if its bad will cauce the same thing .I had a auto repair shop for a about 7 yrs and replaced alot of them when leaded gas was still around.The in sides are a honey come and they come apart and block ehaust flow and couse a large amount of back pressure.You can check it your self with a gauge diff in front and rear of the converter should not be over 3lbs

If the timing was off, wouldn't it have driven poorly when I first got it? This seemed like a progressive problem.

You may be able to tell if its bad by banging on it and lesten for any thing rattling around .

It doesn't hurt to verify the cam/distributor timing in relation to the crank. Sometimes...it is speculation which causes the solution to be elusive.

I've got a timing light but I can't find the spec anywhere. What sort of timing am I looking for? And once again, if the timing was off wouldn't it have ran poorly when I first got it? Or can it just move on its own?

Thanks

You can manually rotate the engine so the harmonic balancer is at 14 degrees. Then take off the distributor cap and it should be pointing at the number one post. If it is, then the motor is timed.

Like I said check the cat I bet it bad they will idle fine but as you increase rpm then the broken pc get blocking the exhoust flow and will not let ot rev up.Then they will pop out the intake like they are out of time.

dobbs571 said:

Like I said check the cat I bet it bad they will idle fine but as you increase rpm then the broken pc get blocking the exhoust flow and will not let ot rev up.Then they will pop out the intake like they are out of time.

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X2, I have had that same problem from a clogged exhaust / clogged cat twice on my own vehicles. Another possibilty is a bad TPS signal wire running to the ECU from the TPS. To check you would need to pull the ECU down and get to the TPS to ECU wires, turn the power on, engine off and do the TPS voltage tests at the ECU connector instead of at the TPS.

Like I said check the cat I bet it bad they will idle fine but as you increase rpm then the broken pc get blocking the exhoust flow and will not let ot rev up.Then they will pop out the intake like they are out of time.

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That is exactly what it's doing. I will be checking it today. I would have never thought to check the exhaust, it will be funny if it is that simple. :laugh3:

Well, it's not the cat. There's nothing blocking it and I even started the Jeep with the exhaust disconected from the cat back and it ran the same, just much louder.

I decided to check the timing next. I followed the directions in my Haynes manual for finding TDC. The rotor is not pointing directly at the number one post likes it's supposed to be. It's a little to the left. Here's a picture:



The mark on the left is for the rotor and the mark on the right is directly under the number one post. How do I adjust the distributer to fix this?

Thanks

Remove the distributor and rotate the rotor one tooth counterclockwise. That's assuming that the engine is at TDC on the #1 cylinder.

Holy crap this thing is driving me crazy! :skull1:

I tried to adjust the distributer but it just keeps ending up in the same place. I've got the timing mark on the crank at 0 as per the haynes manual. I also adjusted the oil gear drive slot that the distributer seats into to try some different positions but got nothing. And I have a hard time believing that the timing would just move on its own. Remember the Jeep drove fine for about a tank of gas before all this started happening.

Somebody please help me get this thing moving!! PLEASE!

I've seen renix motor where they cut the hold down tab off & used a ford style distributor hold down so you could adjust the timing,maybe to cure the same problem you have? it sound hokey but it evidently works.I don't know if this will help you or not but good luck. I'd think it had jumped time if you hadn't checked that out already.

The gear and shaft rotate as you slide the dizzy in place, so you need to point the rotor further counter clockwise like about 2 o'clock to get it right.