Rough start, rough idle, stalling

[Art Garcia]

Lately upon starting my sport Trac. It idles rough making the RPMs drop. Sometimes they drop so low where my truck stalls. It drives fine but sometimes when I get on it, the front window seems to fog up. Also when my AC is on it will cycle from vents to window defrost. In thinking it might be the PCV elbow.



There are no CEL codes



2001 Sport Trac job 2 with 190k

 

[Ed Fenwick]

Look around under the hood for a vacuum leak.

 

[swshawaii]

Arturo- If you haven't yet at 190K, clean the IAC, throttle body, and MAF sensor.

PCV valve and elbow are always suspect to cause running issues, check them.

 

[Greg Jorczyk]

I had the exact same problem on my 2003 with 110,000 miles. I then cleaned the throttle body and it now idles like the engine is brand new. It is very easy to clean the throttle body



Greg

 

[EddieS'04]

Check the vacuum hose under the dashat the glove box. If it is off or broken. That will caise the plenum doors to switch. If it does it on acceleration. Check the vacuum ball in the fender well for cracks or loose tubing. Or a bad checkvalve. That could also be the rough idle and stalling. Vacuum leak.

 

[Richard L]

Very common problem for a rough idle is a dirty IAC (Idle Air Control) and/or a dirty throttlebody. Both are easy to clean. It could also be the the cracked PVC elbow, or a combination of all three..:grin:



As for the AC vaccuum doors opening and closing erratically, the could be related to the cracked PVC elbow, but I am leaning more towards Eddie's solution...cracked or loose vaccuum hose under the dash.



...Rich