i change the coil on the # 4 cylinder den check the spark plugs which they were all good and reset the ecu, but check engine light still on and had it diagnost again and came out still misfiring ,.. so n e of u guys had the same problem maybe could help meeh fix it?????

 

What sparks plugs are you running??? might be wrong heat range also if your turboed or supercharged it might be the gap in the plugs...

 

I have the same problem. Did you have a race header installed recently?