Hi, I'm a new member here and I have a serious problem on my GP. Is a 2001 GT with 111,000 miles.A weeke ago I began to feel like I was loosing power on mi car. When you press the gas pedal you don't feel any respose from the car. Example of this in the higway with the gas pedal press all the way down the car was only 25mph and you don't see the revolutions going up. Other esxample if I'm going up hill I keep pressing the gas but the car keep dying like no power or no change in the trasmision. I perform a test with the car running like 25 miles I switch to neutral and press the gas an the acceleration in neutral in fine. I never change the trans oil but it has new plugs and gas filter. Any idea what could be wrong with it? Please help

Catalytic converter is clogged, you need to get it replaced. There was a recall on some GP's but not sure if 01's were part of it but it's something to look into. Otherwise just get it replaced and find a place to get your old one recycled, they should pay you around $50 for it depending on where you live.

Other than that, welcome to the site!

Here's some info for you: Advisory for All \'01-\'02 Grand Prix with SII 3800 Engine Concerning CAT Converter

If for some reason you can't get it replaced under warranty, consider upgrading to a high flow cat: MAG 23405

Yea, my 02 gp had that problem two months after I bought it. I don't think its under warranty for you because the dealership that did mine said its warrantied up to 76,000 miles and you have over 100,000 miles. Maybe they have changed it because I had mine changed back in 2005.