2000 Mercury Mountaineer, rough cold start

Whenever I start my mountaineer up for the first time each day it runs like a dog. I always have to hold my foot on the accelerator for it to stay running but if i put it right into reverse or drive it will idle fine. And it only happens if it has been sitting for a good period of time which is mainly at night. Ive cleaned my MAF sensor and that hasnt helped. Any ideas what you think it could possibly be.

Whenever I start my mountaineer up for the first time each day it runs like a dog. I always have to hold my foot on the accelerator for it to stay running but if i put it right into reverse or drive it will idle fine. And it only happens if it has been sitting for a good period of time which is mainly at night. Ive cleaned my MAF sensor and that hasnt helped. Any ideas what you think it could possibly be.


Have you tried cleaning and testing the IAC?

I have not, how would u test it,

I just cleaned it, and it still does the same thing, any other thoughts on what to try next.

Even though you cleaned the MAF/IAT sensors, it could still be bad.

I've replaced the MAF sensor earlier and it didnt fix it, is there any way i can just test the IAC before I replace that too. Also I've heard the EGR valve could be the problem, is that possible.

How many miles are on this SUV?
Is the CEL on?
Do a Google ''Youtube auto clean IAC''
Consider doing a smoke test for unmetered air leaks.