Idle control
P0506
Idle Air Control System RPM Lower Than Expected
The engine is idling faster or slower than the computer is asking for.
Fine to drive
Can I keep driving? Yes, in most cases. It won't hurt the car in the short term, but get it fixed. A check engine light that's already on can't warn you about a new problem. It's safe to drive. A low idle can stall at stops. A high idle makes the car creep forward more.
Common causes
- A dirty throttle body
- A vacuum leak
- A sticking idle air control valve on older cars
- A throttle body that needs relearning after a battery change
Listed roughly from most to least likely. The same code can have different causes on different cars.
What to do
- Have the throttle body cleaned.
- Check the vacuum hoses for leaks.
- Ask for an idle relearn if the battery was recently disconnected.
General guidance. Your owner's manual wins. If a red warning light is on or the car drives differently, stop safely and get help.
Related codes
Track this automatically in Tagwell Auto
Tagwell Auto keeps your car's service dates and mileage, so when a code shows up you know what was done last. With a Bluetooth reader for the car's diagnostic port (called OBD-II), the phone app can read the code itself.