Intermittent Cold Start...

[buguhrich]

My m20 just recently started acting up on me when its cold. After sitting overnight, when I try to go out and start it, it takes about 4-5 minutes of cranking before it finally fires. Once it fires, it runs VERY rough at about 500rpm before finally going up to 1,500rpm like it should to warm up.

Also, intermittently, the engine will completely cut off while on the highway then about 2 seconds later kick back into life and run perfectly fine.

Any ideas? Thanks!

[jlevie]

If those symptoms happen to be related, a possible cause could be a bad fuel pump relay or failing fuel pump. But they may be just coincidental and have different causes. Hard starting and a rough idle on a cold engine in the winter is most commonly caused by an intake leak or bad DME temp sensor. The cutoff problem when driving can be any of a number of things.

[buguhrich]

Thanks jlevie.

I thought about the fuel pump and had never replaced it before. I just recently put in a new one and still seems to be having the same problems.