Hey Scotty I own a 2003 malibu 3.1 with 223k miles. I have a random misfire code and cant figure out why. I replaced all plugs and wires, ignition coil, map sensor, cleaned throttle body and maf…

Steveng3669

Hey Scotty I own a 2003 malibu 3.1 with 223k miles. I have a random misfire code and cant figure out why. I replaced all plugs and wires, ignition coil, map sensor, cleaned throttle body and maf sensor still the problem exists.I plan on smoke testing for a vacuum leak in the lower intake manifold since I'm sure there's no vacuum leak anywhere else. Any ideas? Or advise?

Comments (7)
No. 1-2
Steveng3669
Steveng3669

Yes definitely was lower intake gasket. Thanks Scotty you da man

Scotty Kilmer
Scotty Kilmer

Editor

often intake, but also weak fuel pumps do that, as can blowing head gaskets or any intake gasket. good luck