Code P0507, P1400 (idle air control valve)

Hi,

The codes are both related to idle speed. The vehicle doesn't have a traditional idle air control valve. In its place is a throttle actuator control motor (TAC).

The most common cause of this type of issue is an engine vacuum leak or carbon build-up on the throttle body bore or throttle plate.

Check to see if there are any vacuum leaks, specifically the PCV hose between the air intake tube and the valve cover gasket. See pic 1.

Here is a link that explains how to locate and repair a leak:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

If that is good, remove the air intake tube and inspect the throttle plate and bore to see if anything is causing the plate to not close. Also, you may want to service the throttle body.

Here is a link that explains how it's done:

https://www.2carpros.com/articles/throttle-actuator-service

Let me know if this helps and what you find.

Take care,

Joe

See pic below.