Can I clean the IAC valve?

Yes — remove it and spray the pintle and port with throttle body cleaner. This fixes P0505 about 60% of the time.

What is normal idle speed?

Most engines idle at 600-800 RPM when warm. Higher or lower than this range indicates an idle control problem.

Medium Severity

Engine System

The idle air control (IAC) valve is not maintaining proper idle speed.

Common Fix

Clean or replace IAC valve

Estimated Cost (DIY)

$10 - $80

Carbon-clogged IAC valvelikely

Failed IAC valvepossible

Vacuum leak affecting idlepossible

Dirty throttle bodypossible

Need to read or clear this code?

Can I clean the IAC valve?: Yes — remove it and spray the pintle and port with throttle body cleaner. This fixes P0505 about 60% of the time.
What is normal idle speed?: Most engines idle at 600-800 RPM when warm. Higher or lower than this range indicates an idle control problem.

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