Compression test results
#2
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Year: 1996
Model: Cherokee
Engine: 4.0
that is very low, does it even run? they should be around 150 psi. try it now with a wet test. squirt a couple shots of oil in the spark plug hole right before you test a cylinder. if it goes up more than 10-15 psi, then the rings are shot. make sure you have an o ring on the end of the tester and the gauge is reliable to.
#3
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Year: 1989
Model: Cherokee
Engine: inline 6 4.0L
Its not in psi. I'll go check how its being measured. Runs fine. Rebuilt a while back. Idles a bit low, but I cleaned the IAT I think its called, and I think that fixed it. Can't get it to start atm for whatever reason.
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#9
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Year: 1987
Model: Cherokee
Engine: 4.0 liter RENIX I-6, DIY Cold Air Intake, 2.5 FM Exhaust, 3 Core Radiator
I compression tested mine when I first bought it. It had 185K and the average among all the cylinders was 170.
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Year: 1996
Model: Cherokee
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do the wet test as i described above, that will tell you if its rings, to have all cylinders that low is probably rings, or bad tester. does it run? it really shouldn't with those numbers.
#11
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Year: 1989
Model: Cherokee
Engine: inline 6 4.0L
ha maybe I'm not doing it correctly? 230000 miles, replaced cam, crank, 2 pistons, all rings and bearings, oil pump, water pump, starter, and radiator in last 2 months. It has been driven frequently since then, I've just been trying to figure out why it has been idling so low. IAT I'm pretty sure. I don't think my engine is dead.
#12
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Year: 1996
Model: Cherokee
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do you mean iac, iat is intake air temp, iac is idle air control. but cleaning the throttle body is important on jeeps.
your tester may be bad, or the o ring on the end that goes in the head goes bad leaking pressure showing low readings some times.
but if they are that low i'd be worried, is your battery strong when you test, and are you letting it crank 4-5 times?
your tester may be bad, or the o ring on the end that goes in the head goes bad leaking pressure showing low readings some times.
but if they are that low i'd be worried, is your battery strong when you test, and are you letting it crank 4-5 times?
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Year: 2000
Model: Cherokee
Engine: 4.0 I6
ha maybe I'm not doing it correctly? 230000 miles, replaced cam, crank, 2 pistons, all rings and bearings, oil pump, water pump, starter, and radiator in last 2 months. It has been driven frequently since then, I've just been trying to figure out why it has been idling so low. IAT I'm pretty sure. I don't think my engine is dead.
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