2000 Grand Am Gt Problem HELP!

skylarking
Fri, 01 Aug 2008 04:26:54 +0000
Maintenance/Repairs

The car has 152k on it and I love it. It’s been very reliable. Recently I’ve had this problem where I’m driving and the tachometer goes crazy. It goes from 2-3k to 4 to 5 k to 1 k and back really fast. When it does this I lose some power and then it will be fine for a bit then do it again. Sometimes my car drives with no problems for 10 minutes or so, then it will do it again. It’s become worse where the car stalls, but will fire up. The check engine light never comes on. My mechanic (who I trust) replaced the alternator. It drove fine for 30 mi, then did the same thing. He checked the fuel injectors, replaced an “o” ring on one, Nothing. He replaced the ignition, drove it around town for a day and it was fine. I picked the car up and it drove fine for 20 mi then did the exact same thing. The problem is the engine light never comes on so it’s had to detect what is failing. He said that when it does it, his computer says it’s the #2 cylinder that is misfiring. The car fires up fine, idles fine, drives fine, but then seemingly at random it misfires and the tach goes crazy.

I’m sure he’s checked plugs,wires, etc.

Any ideas as to what is failing and why the Check Engine light never comes on when it does this? This has happened on the freeway doing 70 to driving on the streets. There is no rhyme or reason to when it will do it.

Thanks

4 posts - 2 participants