[Drugar]

Ok, Ive got an odd situation. I have an 2002 Impala LS (3.8) with 108k miles, that has what seems to be a loss of power issue.

In the mornings when I go to work, the car drives fine. Its when I either go to lunch, or when I leave work at the end of the day is when it acts up. I can start the car, and when I pull out of the parking lot and accelerate, I feel a sudden loss of power (almost like something is keeping the car from moving). It accelerate, but its real sluggish like I have no power. I then have to let off the accelerator and I can sense the car "chugging" for about 30-45 seconds, and then the power will quickly return in a smooth action and then it will drive just fine.

At times, if I have been driving the car around town alot, or if I have been traveling, it will do the same sudden power loss during acceleration. The difference here is, it doesnt recover that power until I have stopped and turned off the car for 30 mins to an hour.

Every now and then the check engine light will come on during these episodes, but it wont stay on after the car has been off and restarted.

I truly am at a loss, and I am leary of taking it to the shop as I know its going to be a guessing game, and they will want to replace parts until fixed. I dont want to spend a ton of money to replace parts that may not need replacing. I have thought about the Cat going bad as I have read that the 02's had bad Cats, but would it act in this manner? Could it be the tranny?

On a side note, what type of O2 sensors are used on the 02 impala LS. I am looking to buy new ones, but there is a 4 wire and a 2 wire. Short of crawling underneath, do you guys know?

Any thoughts or ideas would be greatly appreciated.

Thanks,

Mike