P050A
Cold Start Idle Control System Performance
Idle air control
Generic OBD-II
High
What it means
P050A means the engine's idle-air control isn't holding the expected idle speed during a cold start — the ECM commands a higher warm-up idle, but the actual RPM doesn't match. The engine still starts, but you may get rough idle or stalling until it warms up. A dirty throttle body or idle air control valve is a common cause.
High
Can I keep driving? Usually drivable — the main symptom is rough idle or stalling right after a cold start; once warmed up it typically runs normally, but get it checked.
Common symptoms
What you'll notice
- Check-engine light on
- Rough or unstable idle when the engine is cold
- Stalling or near-stall right after a cold start
- Slow to settle to normal idle speed when cold
Common causes
Most likely first
- Faulty idle air control (IAC) valveLikely
- Carbon buildup in the throttle body or idle air passagesCommon
- Vacuum leak affecting idle air flowCommon
- Wiring or connector fault at the IAC valveLess often
- Rarely, a failed ECMLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame data to confirm the fault sets during cold start.
- Clean the throttle body, idle air passages, and IAC valve of carbon.
- Check for vacuum leaks around the intake with the engine cold.
- Test the IAC valve and its wiring; replace the valve if it doesn't respond, then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P050A?+
Usually yes once the engine warms up, but cold-start stalling can be inconvenient or unsafe in traffic, so have it repaired.
Can I just clear P050A?+
It will return on the next cold start unless the IAC valve, throttle body deposits, or vacuum leak is addressed.
Related codes
Often seen with P050A
Read & clear P050A yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX