4.0 Running choppy and rich.
#1
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Year: 1999
Model: Cherokee
Engine: 4.0
4.0 Running choppy and rich.
So a while back when driving down the highway, my water pump blew and the engine stalled out (engine light on immediately). Upon starting the jeep it proceeded to backfire run very rich (very strong gasoline smell and smoke out the exhaust). Brought it back to the shop and hooked up an obdII and it threw one code. P0108 (MAP/Barometric pressure circuit High). After replacing the MAP senor the check engine light has gone off but the problem still persists. Almost seems like the ignition timing is off.
From what I've found, common causes are:
Bad MAP sensor
vacuum leak
Dirty/Bad IAC valve
and possibly even a bad ground going a sensor.
I've given the vacuum lines a once over and cant seem to find a leak. I'll do a proper test tomorrow as well as clean the IAC.
Anyone have any advice for what else it could be? Any advice is appreciated.
From what I've found, common causes are:
Bad MAP sensor
vacuum leak
Dirty/Bad IAC valve
and possibly even a bad ground going a sensor.
I've given the vacuum lines a once over and cant seem to find a leak. I'll do a proper test tomorrow as well as clean the IAC.
Anyone have any advice for what else it could be? Any advice is appreciated.
#2
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
How hot did it get?
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Year: 1999
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#4
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
How are you checking the vacuum hoses?
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#6
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Year: 1999
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Engine: 4.0
So after replacing the water pump, rad, map sensor, coil, spark plugs, cap and rotor it still runs just as bad. The very strong smell of gas is still there when running. Doesn't seem to have a vacuum leak and i checked the valve springs. any suggestions?
Also doesn't it seem weird that this would happen at the same time it dumped all the coolant? it doesn't seem like one cylinder is misfiring it sounds like they all are and its idling around 1100 rpm (usually idles lower).
Also doesn't it seem weird that this would happen at the same time it dumped all the coolant? it doesn't seem like one cylinder is misfiring it sounds like they all are and its idling around 1100 rpm (usually idles lower).
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