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2003 Chevy Suburban 5.3, Z code

  • Bennytwostep
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4 years 11 months ago #44507 by Bennytwostep
2003 Chevy Suburban 5.3, Z code was created by Bennytwostep
The truck developed a miss over 1000 miles. Started out slight, according to owner, and got progressively worse. Misfire was on cylinder 4. My scanner is limited, but has pretty good vehicle specific pids. I swapped 2/4 coils and the miss stayed on 4. **CRINGE** I replaced #4 injector. Still a hard miss. Replaced partner coil #3 and solved the miss accordong to the scanner, but I still have a rough Idle. No MISFIRES ON ANY CYLINDER. Injector 7 command shows 300 ms. Injector 8 command shows 142ms. Injector pw on both banks is right around 3.5ms at idle. Around 60k miles ago I replaced his intake gasket, and I cleaned the tips of the injectors. Ft are well within -\+ 10, but I'm leaning toward clogged injectors. Thoughts? Presently no codes. THANKS !!

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