Supercharged Grand Marq Runs rough

[HITEKBALANCER]

I have an 2003 GM (two valve engine) Vortech supercharged. Ran great for two years. It started a little sputter around part throttle 5 inches vacuum. It finally developed into a bigger problem. When the engine is cold it runs good. After about 60 to 90 seconds driving it seems like you pulled a couple coil power wires off. It seem that it is when the cats heat up and signal the engine. I thought spark at first but the block is not even close to temperature yet. I'm thinking egr or egr solenoid. No trouble codes at all.

Anyone got any ideas before I throw the parts cannon at it?

[SC Cheesehead]

I have an 2003 GM (two valve engine) Vortech supercharged. Ran great for two years. It started a little sputter around part throttle 5 inches vacuum. It finally developed into a bigger problem. When the engine is cold it runs good. After about 60 to 90 seconds driving it seems like you pulled a couple coil power wires off. It seem that it is when the cats heat up and signal the engine. I thought spark at first but the block is not even close to temperature yet. I'm thinking egr or egr solenoid. No trouble codes at all.

Anyone got any ideas before I throw the parts cannon at it?

PM Dennis Reinhart, he may have some troubleshooting suggestions for you.