Hesitation Issues
aluminumpork
01-10-2005, 06:04 PM
I've got an 86 Wagoneer (same vehicle as the cherokee) and it's got the 2.8Carb V6. It's in excellent condition, zero rust, 89,000 on it, no dents, no chips, no nothing. Runs great. Except it has a hesitation issue when giving it gas. Depending on the temperature, the hesitation varies. But at it's worst, I give it a little gas to start from a stop and the idles drops and the engine dies. When it's not doing it too bad, the idles drops slightly but comes back up in sort of "lurching" manner and continues to accelerate fine. It is never a problem if I give it alot of gas. It's kinda like a all or none pedal :).
Anyways, to try and remedy the problem I've replaced and done the following:
New inline fuel filter (it's right on the carb)
New cam driven fuel pump
New vacuum lines to the fast idle, etc
Cleaned the carb with carb cleaner and also did the gas dump cleaner
I also purchased a new accelerator pump, but haven't installed it yet as I haven't gotten around to looking at the book and find out where it is located on the carb and whether it's inside or outside it (hopefully out).
Any ideas from the 2.8 owners? Or anyone for that matter? For some reason I have a feeling the accelerator pump isn't at fault, but who knows. Maybe the cold/fast idle is messing this up.
Anyways, to try and remedy the problem I've replaced and done the following:
New inline fuel filter (it's right on the carb)
New cam driven fuel pump
New vacuum lines to the fast idle, etc
Cleaned the carb with carb cleaner and also did the gas dump cleaner
I also purchased a new accelerator pump, but haven't installed it yet as I haven't gotten around to looking at the book and find out where it is located on the carb and whether it's inside or outside it (hopefully out).
Any ideas from the 2.8 owners? Or anyone for that matter? For some reason I have a feeling the accelerator pump isn't at fault, but who knows. Maybe the cold/fast idle is messing this up.
aluminumpork
01-11-2005, 05:05 PM
*bump* :( anyone?
89ltd
01-12-2005, 05:27 AM
I would check to see that the egr valve is not opening to soon, to test it , try unplugging the vacum line to the egr, plug the vacum line and see if it helps.
gtmud
01-12-2005, 07:53 AM
I think your on the right track with the accelerator pump, if you have a WEBE/CARTER carb they are on the inside. since you are going to openit up, I would suggest a rebuild kit. Has the carb ever been rebuilt? You might be surprised to see how much crud is in the carb. They are simple to rebuild, just remove the carb first! I tried to rebuild one on the engine, not good to drop things into the intake(first time rebuilding) Recommend picking up a couple cans of brakecleaner and a stiff toothbrush. The cleaner is great, leaves no residue and the toothbrush won't damage any thing, but it will get off all the varnish and crad. Makesure that ALL of you jet ports are clean. You can remove them with a large screwdriver (flat) to get a better cleaning. Just follow the instructions, and take your time.
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