Keep getting missfire on cyl 2 & 8 not sure why

[2003gt]

keep getting engine code 300 ,302, 308 thought it was bad gas, new tank with better gas company, still pops on,

tried switching coil plugs, still comes on
checked spark plugs, still comes on

don't know what to do next

just started recently, and with normal driving, raced the car several times and never "feel" anything.....

mods are
CAI
Steeda charge motion plates
Steeda U/D pulleys
93 oct Tune

started happening way after those were all on....


please help

 

[bigcat]

did you check the coil pack, or just the connections?

 

[kooldawg6]

Just got my baby back from the dealer after being there for 3 days. My check engine light came on late last week. The car started and ran fine. I dropped it off and got a call back later that morning asking if I had noticed the car misfiring at all. Told them I noticed nothing. They were saying the code that kept coming up was for engine misfire. They couldn't notice a misfire either. Asked to keep my car overnight and look for other problems the next day. The next call I got was perhaps it was a software problem giving a false code. Just for the heck of it they pulled the valve covers to see if anything looked wrong. They found #5 rocker arm was bent. I have no idea how or when that happened...could it have been that way from day one???? Anyways, I have my car back now with all brand new rocker arms. They replaced all of them incase the others did it soon down the road. The car seems so much more powerful now. Although it could be from the much colder temps(mid 40's) and cold tires, but from a dead stop with TCS on...it broke loose BIG time and fishtailed a second or two(mine is the auto).

 

[2003gt]

really ?

damn......i checked the entire coilplugs and relocated them...the problem didn't follow the plugs....


KoolDawg, did you have any mods when you took the car in ?

i don't have many, but i don't want them giving me a hard time

 

[kooldawg6]

Only performance mod I have so far are the Flowmaster axle backs...so no issues there.

 

[JTGrant]

swop fuel injectors and see if the misfire follows.

 

[JTGrant]

any updates?