Low rough idle at start.and low oil pressure once at operating temp
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Low rough idle at start.and low oil pressure once at operating temp
I have a 1998 jeep chrokee classic and it has a harm time starting most the time you have to hold the gas to get it to start and also for it to run and after a couple seconds you can let off and it will idle ok for a few mins then I give it gas and once the rpms start going back down it acts like it wants to die...not to sure where to start I've been watching videos and searching forums and everyone seems to say something different.and also at start up i have around 40psi oil pressure and once it gets up to operating temp it drops down to about 10psi until you hit the throttle...if anyone could lend some advice I'd gladly appreciate it
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Year: 1998
Model: Cherokee(XJ)
Engine: 4.0L
Has it had a tune up any time recently? Could be a few things related to ignition parts.
Could also be the idle air control valve. Pretty sure that's what its called. Mine was bad and I had those exact starting, idling, and running symptoms
Could also be the idle air control valve. Pretty sure that's what its called. Mine was bad and I had those exact starting, idling, and running symptoms
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If a vehicle that starts ok, runs for a couple of minutes ok, but then suddenly starts degrading (stalling, stumbling, hesitating) these are the hallmarks of a failing/failed upstream O2 sensor. The computer does not use the sensor for the first minute or two during a cold start. But once the computer starts relying on it (after operating temperature gets high enough) the fuel trim calculations will start to get progressively worse (because the O2 sensor is feeding bad information to the computer).
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If a vehicle that starts ok, runs for a couple of minutes ok, but then suddenly starts degrading (stalling, stumbling, hesitating) these are the hallmarks of a failing/failed upstream O2 sensor. The computer does not use the sensor for the first minute or two during a cold start. But once the computer starts relying on it (after operating temperature gets high enough) the fuel trim calculations will start to get progressively worse (because the O2 sensor is feeding bad information to the computer).
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Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
FKPF.
Fix Known Problems First.
You know you have cracked vacuum lines. That will cause you all manner of problems. Start there. Don't go spending money or time on this or that. Fix the known problems first. THEN look at other things.
With that oil pressure I'd do a compression test, too.
Fix Known Problems First.
You know you have cracked vacuum lines. That will cause you all manner of problems. Start there. Don't go spending money or time on this or that. Fix the known problems first. THEN look at other things.
With that oil pressure I'd do a compression test, too.
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Year: 1998
Model: Cherokee (XJ)
Engine: 4.0L
FKPF.
Fix Known Problems First.
You know you have cracked vacuum lines. That will cause you all manner of problems. Start there. Don't go spending money or time on this or that. Fix the known problems first. THEN look at other things.
With that oil pressure I'd do a compression test, too.
Fix Known Problems First.
You know you have cracked vacuum lines. That will cause you all manner of problems. Start there. Don't go spending money or time on this or that. Fix the known problems first. THEN look at other things.
With that oil pressure I'd do a compression test, too.
#9
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Thanks for the advice i will be doing this sometime this week...and if anyone else had any insight I'd gladly appreciate it
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mattphillips90
Stock XJ Cherokee Tech. All XJ Non-modified/stock questions go here
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05-17-2012 11:20 PM
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