rough idle on 94 trooper

i have a 1994 isuzu trooper v6 with an automatic tranny. it has 186k miles on it and i am starting to have problems. I took the car out the other day and noticed after 2 minutes or less a weak and rough idle. i took the car home immediately and while i pulled it up the driveway, the engine stalled. I restarted it no problem and parked it and popped the hood. So far i have checked the plugs wires and coilpack and they are all working ok. i know that my vavlecover gaskets are leaking and checked the oil level and it is fine as well. i checked the alternator and it is charging properly, so that eliminates that factor. the only things that i could think of that would be causing the problem are either that the engine is out of tune and i need to fix the timing, or that i have an electrical short somewhere along the line. any help would be greatly appreciated.

If you have more the 70k on the plug wires I would swap them out.

Every cleaned the injectors?

Last time you changed the fuel filter?

checked the plugs...replaced not too long ago
put full can of injector cleaner in about 3000 miles ago...not sure if thats good enough
fuel filter...ill check it today
thanx for the help!

well i changed out the fuel filter yesterday and the idle has improved a little, but is still rough. im guessing that the fuel filter needed changing because it is running better, but that wasnt the problem, so im gonna change out the plugs and wires. im almost positive that my engine is misfiring, so should the plugs/wires not fix the problem what else should i do? any advice would be greatly appreciated!

This may be a bad intake manifold gasket. I believe you can spray some carb cleaner around the edge while the engine is running. If it revs up a little, then it sucking it through. This was how a machanic diaged this problem on my truck awhile back. The FAQ talks about this, but says to use breake cleaner... I'm pretty sure thats wrong.. carb cleaner should be the way to test it.

there was a recent post in the Rodeo forum, where the owner had some same problem. He did all of the normal plugs, wires, filters and so on. But still no luck. The fix was an 89cent bottle of HEET (that stuff that soaks up water in your gas tank). might be worth a try.

http://www.automotiveforums.com/vbulletin/showthread.php?t=376310&highlight=heet

thanx a bundle for the ideas guys. i will try out that heet stuff and also the intake manifold gasket. i did notice that when i pulled the gas line, for the fuel filter, i was getting milky colored gas coming out. could that possibly be water mixed with gas? anyway i started it up the other day and i noticed that my fuel level was somewhat low...1/8 tank. i do put in arco gas, which isnt the greatest of gas. perhaps i will put a half tank of quality gas in and mix it with that heet stuff. again thanx a ton for the ideas :) and i will keep you guys posted on what happens!!!!

today i bought plugs, wires, an oil filter and some oil and got to work. I changed the oil first because it had been almost 3000 miles and i figured that i had to do it sooner or later so why not? anyway, i changed out the oil and filter and started the car up and WOW!!! :eek: the car was running perfect! i dont get it at all, but hey im not complaining. i have no idea why this happened, especially with the symptoms i've been having and how they happened all of a sudden out of nowhere. anyways, the car is running great and hoppefully that was the end of my problem. if not, i know where to find help :biggrin:

It was probably the wires.

Keep up on the maintaince and it will last a long time!