Jeep XJ unstable idle and black smoke
06-28-2017, 08:27 AM
#1
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Model: Cherokee
Jeep XJ unstable idle and black smoke
My Jeep XJ 2.5 93 model, the problem is:
idle is not constant and the RPM reading is up and down and also black smoke and I can smell fuel. When I press the gas pedal, it sputters.Is it my IAC problem?
idle is not constant and the RPM reading is up and down and also black smoke and I can smell fuel. When I press the gas pedal, it sputters.Is it my IAC problem?
06-28-2017, 09:08 AM
#2
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Year: 1998
Model: Cherokee
Engine: 4.0
I would clean the IAC and throttle body. I would also check the map sensor and the vacuum hose that is attached to it, the vacuum hose is plastic and tends to brake over time. Is the CEL on?
06-28-2017, 09:26 AM
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Model: Cherokee
There is no CEL light.The MAP sensor is new.When I press the gas pedal(punch) the engine struggles to REV and have laggy and misfires.Any injector problem?
06-28-2017, 10:45 AM
#4
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Year: 2000
Model: Cherokee
Engine: 4.0
Sounds like its running rich for some reason, either too much fuel or too little air...could be so many things.
I'd personally start with simply resetting your PCM and refreshing all your grounds first, that stuff can cause havoc.
Check your TPS and especially o2 sensors, but if you don't have a check engine light its most likely not those.
Fuel regulator or injectors would be my last port of call...good luck
I'd personally start with simply resetting your PCM and refreshing all your grounds first, that stuff can cause havoc.
Check your TPS and especially o2 sensors, but if you don't have a check engine light its most likely not those.
Fuel regulator or injectors would be my last port of call...good luck
06-28-2017, 03:21 PM
#5
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
Inspect the hose very closely that runs from the intake manifold to the MAP sensor.
06-28-2017, 10:12 PM
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Model: Cherokee
Sounds like its running rich for some reason, either too much fuel or too little air...could be so many things.
I'd personally start with simply resetting your PCM and refreshing all your grounds first, that stuff can cause havoc.
Check your TPS and especially o2 sensors, but if you don't have a check engine light its most likely not those.
Fuel regulator or injectors would be my last port of call...good luck
I'd personally start with simply resetting your PCM and refreshing all your grounds first, that stuff can cause havoc.
Check your TPS and especially o2 sensors, but if you don't have a check engine light its most likely not those.
Fuel regulator or injectors would be my last port of call...good luck
