Hello people! My Grand Am has rough idle on and off. It was missing a lot yesterday but running smooth at idle for most of today. It bucks when cruising at low rpms on the highway half the time(somewhere between 1500 and 2000 RPMs. It takes a lot of accelerating to get it out of that slump. It also tends to buck and backfire occasionally when accelerating from a stop.
When I start it up, it starts right away, but it either hovers at 900rpms for about 3 seconds before idling normally or it will go up to 900, drop immediately down to like 400, then go to normal idle. In the 2 years I've only it, twice I've tried to start it up and it would not start unless I pumped the gas a little (once last year and once a month ago).
I haven't put new plugs and wires on it. I believe they are the originals. They might have been left because plugs used to last 100k miles. I have no check engine lights. What could this be?
When I start it up, it starts right away, but it either hovers at 900rpms for about 3 seconds before idling normally or it will go up to 900, drop immediately down to like 400, then go to normal idle. In the 2 years I've only it, twice I've tried to start it up and it would not start unless I pumped the gas a little (once last year and once a month ago).
I haven't put new plugs and wires on it. I believe they are the originals. They might have been left because plugs used to last 100k miles. I have no check engine lights. What could this be?
May 26, 2008 at 12:20 AM