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Gas in Oil

Old Jun 24, 2021 | 07:55 PM
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Whiskey101's Avatar
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Default Gas in Oil

Been having problems ever since I bought this jeep. 1999 grand cherokee and I have replaced all the sensors on the throttle body, fuel pump, camshaft sensor, crankshaft sensor, fuel filter, fuel injectors, spark plugs and coil pack. Drove it the other day and it was running rough, I mean really rough. Went through 8 gallons of gas in 27 miles to get home. Stunk of fuel. Excess fuel in oil and intake. Still smells like gas and will not start, just backfires. Any suggestions? I'm at a loss and about ready to throw a match on it!
Thanks guys!
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Old Jun 24, 2021 | 09:14 PM
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From: Lost in the wilds of Virginia
Year: 1998 Classic (I'll get it running soon....) and 02 Grand
Model: Cherokee (XJ)
Engine: 4.0
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O2 sensors?

Which engine?
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Old Jun 24, 2021 | 11:39 PM
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Originally Posted by BlueRidgeMark
O2 sensors?

Which engine?

Has 4 O2 sensors, haven't changed them yet. It has the 4.0L

**Pulled the fuel rail... one injector was stuck open.** Will replace and see if that was the problem.

Last edited by Whiskey101; Jun 25, 2021 at 08:07 AM. Reason: Update
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Old Jun 25, 2021 | 09:33 AM
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Engine: 4.0
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Your O2 sensors are the prime suspects. Check the fuse(s) first, then the wiring.
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Old Jun 26, 2021 | 01:58 AM
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From: Manlius, east of Syracuse, NY
Year: 2000 XJ Sport & WJ Laredo
Model: Grand Cherokee (WJ)
Engine: 4.0L
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I was going to suggest stuck fuel injector, but I saw you replaced them, or said you did. Have you run codes yet?
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Old Jun 28, 2021 | 08:44 AM
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I checked everything and found that I had no compression in #5, #6 or #3 pistons. Was hoping to avoid the inevitable rebuild until winter. At least the problem is now known and I can begin my new adventure with the 242 engine.
Thanks for all the advice it was appreciated.
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Old Jun 28, 2021 | 09:31 AM
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Engine: 4.0
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Originally Posted by Whiskey101
no compression in #5, #6 or #3 pistons.
Yeah, I can see how that might be a problem.....

Have fun with your rebuild!
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Old Jun 28, 2021 | 11:46 AM
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Year: 1997 230,000 miles
Model: Grand Cherokee (ZJ)
Engine: 4.0, new lifters valve job with new springs and exhaust valves, preload set with shims
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[QUOTE=Whiskey101;3649505]Been having problems ever since I bought this jeep.

Whadda ya want for nothing, a rubber biscuit? You bought a 22 year old vehicle, you better expect problems.
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