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1990 Jeep Cherokee 4.0 (Renix) Help

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Old 07-23-2017, 03:04 PM
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Default 1990 Jeep Cherokee 4.0 (Renix) Help

Hi everyone, I have a 1990 Jeep Cherokee with 313,xxx miles. About a month ago it started missing and running really rough so I replaced crank shaft position sensor, iac, tps, map sensor, whole distributor, spark plugs, and spark plug wires. So then that leads me to do a compression test since after I replaced everything it was still missing here's what I got.
Cylinder 1-115psi
Cylinder 2-130psi
Cylinder 3-130psi
Cylinder 4-130psi
Cylinder 5-90psi
Cylinder 6-150psi
Then I read some threads about people having same problem so I pulled the valve cover off and pulled the rockers and Roller Arms none of the Roller arms are bent so what should I look for in a bad Rocker? Or if you have any other suggestions that would be great thanks in advance.
Old 07-23-2017, 03:27 PM
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Is vacuum line to map in good shape a small crack in it can cause issues like this.
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Old 07-23-2017, 07:21 PM
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Thanks I'll try this out and see what happens.
Old 07-24-2017, 08:25 AM
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Originally Posted by Cody90
Thanks I'll try this out and see what happens.
Cody, go to my website also.

Do tips 1 through 5.

Don't worry about the compression just yet. That could just be a result of carbon buildup from a misfire.

Keep the questions coming.
Old 07-31-2017, 01:59 PM
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Originally Posted by freegdr
Is vacuum line to map in good shape a small crack in it can cause issues like this.
Nothing happend when I replaced that and the rest of the vaccume lines what else should I try?
Old 07-31-2017, 02:00 PM
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Originally Posted by cruiser54
Cody, go to my website also.

Do tips 1 through 5.

Don't worry about the compression just yet. That could just be a result of carbon buildup from a misfire.

Keep the questions coming.
whats you website name?
Old 07-31-2017, 06:12 PM
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Originally Posted by Cody90
whats you website name?
www.cruiser54.com

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