A dirty throttle body or IAC passage restricting idle air. A failing IAC valve. A restricted air intake (clogged air filter). An engine running poorly from another fault (misfire, low compression).

Trouble codes › P0506

P0506 Idle Air Control System RPM Lower Than Expected

Q: What does P0506 mean?

P0506 means the engine is idling lower than it should, often a dirty throttle body. The engine is idling lower than the engine computer is trying to make it, even after it has opened up idle air as far as it can.

Fuel and air

P0506 means the engine is idling lower than it should, often a dirty throttle body.

The engine is idling lower than the engine computer is trying to make it, even after it has opened up idle air as far as it can.

Can I keep driving? Yes, but get it fixed soon.

Usually drivable, but low idle can lead to stalling at stops. Get it checked soon.

Common causes

A dirty throttle body or IAC passage restricting idle air
A failing IAC valve
A restricted air intake (clogged air filter)
An engine running poorly from another fault (misfire, low compression)

Symptoms

Low or rough idle
Stalling, especially with the AC on
Vibration at idle

What to check first

Clean the throttle body and IAC passage.
Check the air filter.
Look for other codes (misfires, sensor faults) and fix those first.
Do the idle relearn your service information describes.

What does P0506 mean on your vehicle?

The likely cause depends on your engine. iRepair researches your exact year, make, model and engine (service bulletins, recalls and owner reports) and tells you what to check first. Your first 3 questions are free.

Ask iRepair about P0506

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Related codes

General guidance for P0506 on most vehicles. Some makers use the same code a little differently; confirm in the service information for your vehicle, put safety first, and see a professional when in doubt.