This 1988 c30 5.7L will backfire when warm on acceleration over half [...] in 2nd and 3rd gear(4 speed with Granny Low) Has new cap and rotor. Have tried new ignition coil, unplugged E.G.R., ran in by-pass mode(set timing connector unplugged)which made it wors...

FIX posted 9/17/2012

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