runs worse than before
08-28-2015, 05:25 AM
#1
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Location: Largo, FL
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Year: 1995
Model: Cherokee
Engine: 4.0 HO
runs worse than before
So I removed a motor that made a ton of noise... Ticks, knocks, squeaks and squeals, but still had the power. The newer motor doesn't make any of those noises but it doesn't seem to have the power. It's bogging down when I get to 2k RPMs and over. There is a white vapor coming out of the exhaust (maybe dumping fuel like crazy)... I installed a bunch of upgrades (already had the header back exhaust; installed neon injectors, 99+ manifold and gasket matched the throttle body, header, intake manifold and head) can't imagine it would take to terribly long for the PCM to relearn. I've barely driven it 30 miles so far and have gone through almost a quarter tank of gas.
08-28-2015, 08:24 AM
#5
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Year: 1995
Model: Cherokee
Engine: 4.0 HO
I just built this motor. We basically rebuilt the head. The lower end, I just replaced the lifters, timing chain and oil pump. All gaskets are new.
08-28-2015, 08:29 AM
#6
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
The steam from the exhaust indicates a problem, it's not just normal byproduct of combustion and catalytic converter doing its job steam.
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08-31-2015, 02:10 PM
#9
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Year: 1995
Model: Cherokee
Engine: 4.0 HO
I dropped it offat a shop yesterday, to have them check it out. So far, all they can tell me is that my number two injector is dead; the pcm is supplying voltage to it but it's not firing... Or it could be stuck open. I told him that I just put neon injectors in the for the upgrade and he tells me that could be an incompatibility issue, since it has a different spray pattern
08-31-2015, 09:02 PM
#10
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Year: 1995
Model: Grand Cherokee
Engine: 4.0 with all of the noise and clatter
I dropped it offat a shop yesterday, to have them check it out. So far, all they can tell me is that my number two injector is dead; the pcm is supplying voltage to it but it's not firing... Or it could be stuck open. I told him that I just put neon injectors in the for the upgrade and he tells me that could be an incompatibility issue, since it has a different spray pattern
09-02-2015, 06:31 PM
#12
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Year: 1995
Model: Cherokee
Engine: 4.0 HO
Threw in a stock injector for now; that took care of the idle and throttle issue. Runs way smoother now. Now, for the scary part... Finding out where all of my coolant went.
09-02-2015, 07:34 PM
#13
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Year: 1999
Model: Cherokee
Engine: 4.0
If you are running rough, have white smoke and missing coolant... As Bustedback said above, sounds like a head gasket.
Although you just did this, its possible there was an issue with the gasket
Although you just did this, its possible there was an issue with the gasket