Why does my car stall at red lights?

Low idle speed from a dirty IAC or throttle body cannot keep the engine running when you take your foot off the gas.

Can a dirty throttle body cause P0506?

Absolutely — carbon buildup restricts airflow at idle. Cleaning it is the first thing to try.

Medium Severity

Engine System

Idle speed is too low. The IAC is trying to raise it but cannot.

Common Fix

Clean throttle body/IAC

Estimated Cost (DIY)

$5 - $80

Carbon buildup in throttle body/IAClikely

Vacuum leakpossible

Failing IAC valvepossible

Need to read or clear this code?

Why does my car stall at red lights?: Low idle speed from a dirty IAC or throttle body cannot keep the engine running when you take your foot off the gas.
Can a dirty throttle body cause P0506?: Absolutely — carbon buildup restricts airflow at idle. Cleaning it is the first thing to try.

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