Hello All,


New guy here from Waxahachie, TX. I've been fighting a P0300 on my '06 Silverado, off and on for a few years. Usually, I can reset it and pass inspection. Now, it's misfiring constantly at idle. Goes away at 1,000 RPM and up. I've fought it since March of this year, and finally figured I'd have to just disable it, until I can get it properly fixed. I taught myself PCHammer and TunerPro with the help of youtube and this site. I figured I'd sign up as a member so that I can learn more about ECM programming. I want to do a Stage 2 low lift cam next Spring, and plan on doing all of the work myself, including the tune. I also have a '64 C10 that will get an LS one day, so anything I can learn before then will help greatly. I'm a big "do it yourself" guy, and do all of my own mechanic work, since I was 15, so this P0300 is killing me. I've done, plugs, wires, coils, injectors, vacuum tested my cats, O2 sensors (replaced but one flat lines at idle), springs and valve seals, new intake manifold gaskets, new MAP, new evap purge, and lastly, cleaned MAF and throttle body. Still constantly misfires on #3, and #4 at idle. I'm thinking maybe a bad set of lifters or flat cam lobe.


Thanks for having me,
Judd