No cure for Rough idle..

[SeniorGustas]

So ive done just about everything.. I had a gassy smell from my car and a really rough idle. First i replaced cap rotar and plugs. No improvement, then emptied out my tank and put fresh gas in with a new gas filter. still horrible.. then i went to fuel injector.. still nothing. I ordered in new plug wires and they should be here today along with an O2 sensor.. any ideas on what else this could be from. oil was replaced not to far back maybe 200 miles and i have a full fluid flush 4 months ago.

[4.3LXJ]

Checked compression yet?

[Paddletrucker]

Could the throttle body and IAC need cleaned?

[SeniorGustas]

I still do not have vaccume resviour. could that be the problem? it could be sucking in dirt from my wheel well.

[nickyg]

I still do not have vaccume resviour. could that be the problem? it could be sucking in dirt from my wheel well.

Do you have an open vacume line? that might be the problem.

[SeniorGustas]

So if anyone was wondering i cured it!! muhaha victory. After replacing about $400 in parts i found one small vaccume hose that was cracked near the fuel injector.. not sure it was vaccume or fuel? when i plugged the far end while the car was idling it shot gasy oily shhhtuf out. so went to the auto parts store and picked up a new one for $1.25 :bang: :bang: but all those parts would have needed to be replaced soon enough anyway! felt great to hear it sound happy again pulled up a chair and watched her idle :beer: Thanks for all the tips guys i have pictures if needed but this thred wasnt to popular so may not post em

[89Laredo]

Post a pic... sounds almost like the vac line for the FPR, which SHOULD NOT have fuel in it.

[SeniorGustas]

oppps haha ill do it right now.

[SeniorGustas]

2072

[89Laredo]

Why is your vacuum block back there?
Are you sure its fuel coming out of that line?
Follow that line and you should find the FPR:
http://i879.photobucket.com/albums/ab356/organicep3/IMG_0495.jpg

Start it and let it run, pull that vacuum line off (cap it with your finger after you pull it off) and see if fuel comes out. If so, you need a new fuel pressure regulator. There should be absolutely no fuel.

[SeniorGustas]

its back there factory. i have the I4 its held up by a metal rod thing. haha idk. will do not sure what it was i'll follow it and let you know

[ALS XJ]

Hey Adam, your info says 4.0 not I-4, hence the mix up...I'm having idle issues as well. My 92 will nearly stall (about 450 rpm), then rev itself to about 1200 rpm. So far cleaned TB, installed new gasket, new IAC, new TPS, new cap, rotor, coil, wires and plugs. This happens about a minute or 2 after start-up...for about 10-15 minutes, then goes away! Whacky!!!!!! Anyone out there who has a fix? Please........

[SeniorGustas]

Oops! thanks for that, ill change that hadnt noticed. Not sure while i had this problem my car would idle very high then die down. being a later modle no idea of rpms but probaly was idling about 1,500. i would go through and check all of your vaccume lines. may change something or an 02 sensor im new to most of this stuff so i may not be much help but doing this process on mine i found a few vaccume lines that were dissconected which made for a much smoother idle while this was happening! best of luck and keep me posted when you figure out what was wrong

[ALS XJ]

OK...I just replaced my O2 sensor...problem seems to have gone away. The '92 is ideling at the usual 750rpm. So far, runs fine again. Once again, Steve...you are a guru. Thanks man.

[ALS XJ]

Here was my idle problem...drove me crazy!!!::bang:
Jeep would start fine...about 1 minute into idle, it would sputter and almost stall, then immediately rev to about 1200rpm (hydrocarbon would spew from the tailpipe). This would repeat over and over. When the throttle was mashed, jeep would sputter again and almost stall (real dangerous when pulling out into traffic!). Here was my fix: O2 Sensor! After replacing almost everything else (IAC, TPS, entire tune-up including coil and wires, thorough TB cleaning and gasket replacement)...a 5 min. fix did the job!:cheerleader: Hope this post helps anyone else with this strange idle issue.:beer: