I have a 2002 trans am with 36000 miles on it.
Mods ms4 cam (biggest one)
long tube headers no cats true duals

Last year when i took it out of the garage it was misfiring for about a month, i scanned it with a hand held scanner and said random multiple cylinder misfire. Then it just kind of went away and drove completely normal for the rest of the year. This year I took it out of the garage the other day (i store it in the winter)and went for a drive and it was running like crap misfiring pretty bad when i'm at a constant speed but when i punch it, it seems to clear up.
I thought it might just be bad gas cause it has been sitting for a couple months but i put seafoam in it and put about 8 gallons in it and i was still running bad. I felt the headers and drivers side was warm and passengers side was hot. Then i changed the plugs and that didn't help either. My next options were going to be change the wires and check the coil pack voltage?
Does anyone have any ideas what could be wrong?

 

I guess I would start by checking my grounds.

 

compression test?

 

you didnt mention about tune after cam install did u have it tune?