ZJ S.O.S.!!
#1
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Year: 1997
Model: Grand Cherokee
Engine: 4.0
ZJ S.O.S.!!
Well i thought i knew everything about my 97 zj 4.0.(about 170,000) Man was i wrong. Anyways, i noticed loss of power and a rich smell one day while driving. I gave it a tune up, still there. I brought it to get the code check and came up as 02 rich. We also noticed a winding sound coming from the intake manifol area and they told me it could be a manifold gasket problem or leaking vacuum hose, and my hoses were all good so i bought a new gasket and changed it. Problem still there. I changed the intake manifold thinking it may be cracked. The problem is still there! I cant get an inspection and the thing still drives and runs ok. Its driving me nuts. Anything else i can try cuz im ready to get a new motor next. Any help would be great. Thanx
#2
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Year: 1994
Model: Cherokee
Engine: 5.2
with it running spray some carb cleaner or something similar around seals under hood. If you hear a change in idle that is where the leak is. It will suck in the spray and cause a change in idle.
#3
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Year: 1997
Model: Grand Cherokee
Engine: 4.0
ZJ S.O.S.
Already tried that. Sounds like its coming from in the block. I can hear it near the intake manifold. Almost sounds like a fan running at the same rpm as the motor in the intake.
#4
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Year: 1993
Model: Grand Cherokee
Engine: 4.0
propane
i seen the post of carb cleaner but have you tried a small propane tank with a small hose attached its dangerous but it zeros down the area where a leak would be likely?????? a bit better than carb cleaner?
#6
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Year: 1997
Model: Grand Cherokee
Engine: 4.0
ZJ S.O.S.
I have no cracks outside the motor pulling in air and no bad vac hoses. If its a fuel injector prob, could it be a map sensor? The injectors are all running.
#7
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Year: 1997
Model: Grand Cherokee
Engine: 4.0
ZJ S.O.S.
Oh, and I have no gas smell. I get the sooty tail pipe and bad smelling exhaust. It runs pretty smooth when first started(with the smell), and when it warms up it revs almost like it has bad timing
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#9
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Year: 1993
Model: Cherokee
Engine: 4.0L I6
Sounds like a cracked exhaust manifold to me they crack where the two goes to one at the flange. Its also makes the o2 see to much oxygen so it rich'ns the mix.
#10
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Year: 1997
Model: Grand Cherokee
Engine: 4.0
ZJ S.O.S.
I have a header on it thats about a year and a half old with a brand new gasket. Im not getting any loud exhaust sound either.
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Year: 2004
Model: Grand Cherokee
Engine: 4.7L V8
If I had a similar vehicle to use as a donor, I would try switching sensors and see what cured the problem.
Dan