I have a manual 2000 mustang V6, and the idle surges up about 200 rpm every thirty seconds or so. I notice it in neutral, and in gear with the clutch in. Is this a common problem? Is there a common fix, I only noticed it recently in the cold weather?
Could just be the engine warm up. I haven't had my V6 in cold weather yet, got it 4 months ago and it is still 80+ in Houston. But my older 93 stang would do that when it finally got cold down here.
I replaced the battery (it was the orginal that came with the car 6 years ago), now it idles smoothly. Cold probably brought out my battery problems, it was beginning to crank for a while before turning over too, so I just figured I'd replace it now before it becomes a refuses to start when it's 10 degrees out, there are three feet of snow on the ground, and I'm late for work.