Rough Idle


#1

I have a 2001 Ford Escape, and when I start it for the first time of the day, it idles really rough, and way below 500RPMs (to the point where it almost stalls). After about 10 minutes, when the car is all warmed up, it runs smoothly, as if there was nothing wrong with it. The only conclusion I can draw is that it is temperature related, but I can’t figure out exactly what is causing the issue.

Any suggestions?

PS: This happens on the driest or wettest of days, so moisture doesn’t seem to be an issue.


#2

I wonder if there could be a small leak in the fuel system, letting air in the system?


#3

The ECM is supposed to take temperature signals from the air intake and engine and use those to adjust the fuel mixture a little richer during “warm-up”…If this is not happening, for whatever reason, the engine will run rough until it warms up…