iXephoz

Hey everyone, I have been having problems with my 02 GT. It seems to run rough once the engine gets warmed up, and how I can basically describe it is that it "Bucks" while driving. Especially in lower RPM's. When I take it past 3500 it doesn't have this problem, but when I am low like 2000-3000 it has this problem. I can here it in the exhaust, the car seems to buck. Especially when it is going up a hill. Does anyone know the problem? Only engine work is a CAI, that's about it. Ever since I bought the car it's been like this.

iXephoz

Forgot to mention that it's a 5 Speed

99GTvert

How many miles are on it? Plugs still stock?

dawson1112

One thing I know about the OBDII system is any miss or ignition problems will set some kind of DTC , the light may not come on and stay on and it may only flash for a second , but it will have stored a code in the computer. Have it scanned for trouble codes .

iXephoz

It's got around 130,000 miles. My Dad replaced all the coil packs recently, no luck. As far as CEL, nothing came on yet. But the cars been running like this for awhile and I'm worried

RMK01GT

zip tie the electrical connectors on the COP's

I had a similar issue and was thinking maybe bad COP? maybe bad plugs?

turned out to be a loose connection (not visable just very slight play in the connector) and was surprised the difference that made.

iXephoz

I spoke with my Dad again. He only replaced 2 coil packs, but changed all the spark plugs. He thinks it's water getting around the plugs and making them short out causing a misfire.

Maddsajin

what kind of spark plugs did you use??? i just fixed my 03 GT becuase i put in the wrong spark plugs... what kind ya got...

ESABATM

Unless you have an intake leak allowing coolant to get in the plug wells that's doubtful. I would check your fuel pressure at the rpms where it happens.

Does it do this only when driving or can you recreate it in the driveway by manipulating the throttle?