1999 4.3 with P0300

By estebbin
May 12, 2006 in Ask A GM Technician

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estebbin

Posted May 12, 2006

I have a 99 C1500 4.3L, 104K and it has a P0300 code. What's new, Coil, masair, plugs, cap, rotor, dist. gear and new timing chain. What could be causing my misfire code? Has a lack of power and noise coming from the air cleaner. Need help and pin point test.

ChevyTech007

Posted May 14, 2006

Sounds like a clogged cat converter. You need to do a back pressure test

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