Car running like crap! Help

[bigDogs02GT]

Had to send the Xcalibrator back to MPH due to detonation and after reflashing computer with original factory tune my car is running like s**t. Between 1000-1500 the damn thing bucks and surges. Seems like it is misfiring. Anyway I am taking it to the dealer tomorrow. Does anyone have a clue as to what is wrong? No SES lights either. Dealer said they would change the plugs and a tune up for $150.00 and if it doesnt fix it they will do a complete computer diagnosis for $95. I'm just looking for some possible solutions before it costs too much. Sorry for the long thread.

 

[Roger_4.6_96]

Had to send the Xcalibrator back to MPH due to detonation and after reflashing computer with original factory tune my car is running like s**t. Between 1000-1500 the damn thing bucks and surges. Seems like it is misfiring. Anyway I am taking it to the dealer tomorrow. Does anyone have a clue as to what is wrong? No SES lights either. Dealer said they would change the plugs and a tune up for $150.00 and if it doesnt fix it they will do a complete computer diagnosis for $95. I'm just looking for some possible solutions before it costs too much. Sorry for the long thread.

I never got a code when my car missfired. Check your plugs and cops.

 

[bigDogs02GT]

How can you tell if your COP is bad? The dealer is going to change the plugs tomorrow so I'll find out if they are bad.