Engine will not idle, starts and runs for a moment, then shuts off

RENEACONTRERAS

MEMBER
2003 FORD FOCUS
2.0L
4 CYL
2WD
AUTOMATIC
200,000 MILES

I must accelerate the engine above idle to keep it running. If I release the gas pedal it shuts off. I had a P1401 code, I replaced the EGR Pressure Feedback Sensor and it cleared the code. Could the Idle Air Control Valve be at fault?

The issue began after I cleaned the Mass Air Flow Sensor. I used the CRC MAP aerosol cleaner while running the car. Prior to the cleaning the car idled a little rough and would stall out.

(2.0 Liter ZETEC Dual Overhead Cam)

Can you advise please? Thank you

Rene Contreras

3 Replies

STEVE W.

MECHANIC
12,967 POSTS

Hello and welcome to 2CarPros. From your description it sounds like the issue started right after the cleaning? Cleaning the MAF with the engine running may have damaged it, there is a couple ceramic parts inside that sense the airflow using the amount of current the sensor uses to keep a small heating element warm. It is possible the cold spray thermally shocked that and it failed. Another possibility is that the system now is confused because it has a clean sensor and it's telling it the wrong numbers for the airflow.
A test you can try, disconnect the battery negative lead. Leave it off for a few minutes. Reconnect and see if it relearns the idle position and idles correctly now. It might take it a bit to learn the idle as it usually needs a warm engine.