Originally Posted by
scottyielding
I am new to tuning so please forgive me if my questions are remedial or may even sound stupid to some of you.
I have a 2002 LS1 that has been stroked (383), heads, cam exhaust ect... I can list the specs if needed. I had it running decent but changed a few items and know I am having an issue.
I changed injectors, coils, throttle body, intake and MAF sensor. now the car sets P0300 for random misfire. It may have been doing it before but I do not think so. I have not driven this car in about a year. The car idles fine and does not seem to have a misfire but the computer says that it does. I am showing random misfires on every cylinder (according to GMs scan tool) but just 1-5 times pre cycle. On #6 I am showing 25-50 per cycle. This is at idle. If I raise the RPM to 1000-1200 I only show misfires on #6 and it is only 10-20 per cycle then. I thought it might be a coil at first but if it is a coil I would expect it to get worse at higher RPMs and my coils are almost impossible to access or I would just swap one. I did swap the plug to a different cylinder but nothing changed.
I don't really think the car has a misfire and I know the tune is WAY off at this point but I am hesitant to start tuning the car if i might actual have an issue. I say all of this to ask this question. If the tune is way off can it cause a false reading of a misfire? Please give me your advise and keep in mind I am a novice to tuning but I have been playing with cars for over 25 years.