Questions and Answers

Pontiac Grand Prix Sluggish, Bogs Down Q. I have a 2001 Pontiac Grand Prix GT with a 3.8 liter Series II engine. It has just over 50,000 miles on it. In the last two weeks it has been sluggish, also at 4,000 rpms it bogs down and there is a rapid ticking or knocking sound. The tachometer doesn't show the rpms dropping off but it won't accelerate. If I back off on the throttle, it goes back to almost normal acceleration.

The Check Engine Light blinked rapidly for about 10 seconds the first time it happened, but has not come on since. I put in a fuel system treatment with fuel injector cleaners and changed the fuel filter. That helped the sluggishness a little, but it still has the same problem at 4,000 rpms.

At the parts store they also hooked up at tester to check the battery and alternator, which were fine. Without the Check Engine Light on they won't hook it up to a diagnostics computer. Do you have any ideas?

Thank you,
David

A. The flashing Check Engine Light (MIL) indicates a possible catalyst damaging misfire. The catalytic convertor may be partially clogged and causing it to "hold back". You may want to see a dealer about this, they are covered for 8 years or 80,000 miles usually. Just a guess but worth looking into.