Misfire cylinder number six

2002 CHEVROLET TRAILBLAZER
240,000 MILES • 4.2L • 6 CYL • 2WD • AUTOMATIC
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RENE C
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My dog shewed on the cables of the ABS unit. ABS and brake light came on. Got under truck and reconnected the chewed cables, but the light didn't turn off. Suddenly I began having a misfire on piston #6. Changed plugs, swapped coils, changed coil connector plug, checked for air leaks, compression, injector, and nothing. The misfire continues. I truly need help solving this mystery.
Thanks,
Rene C
Apr 15, 2021 at 1:57 PM
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ASEMASTER6371
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Good evening,

I would check the fuel pressure to be sure it is not low. Low pressure from a weak fuel pump will cause the misfire.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

What was the compression? It needs to be 140-160 pounds.

Roy
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Apr 15, 2021 at 5:06 PM
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RENE C
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Hi Roy, thanks for responding. Compression is at 149 lbs. Could there be a relationship between the ABS module and the number six cylinder misfire?
Apr 15, 2021 at 5:33 PM
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RENE C
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Will check fuel pressure next. Thanks!!!
Apr 15, 2021 at 5:35 PM
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ASEMASTER6371
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No, no connection.

Keep me updated.

Roy
Apr 15, 2021 at 5:37 PM
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RENE C
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Will do Roy. Thanks again!
Apr 15, 2021 at 5:38 PM
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ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
Apr 15, 2021 at 5:42 PM