TORQDEX // POWERTRAIN DTC
Idle Control System Malfunction
A general fault has been detected in the engine idle-control system.
00 // CODE DEFINITION
What P0505 means
P0505 indicates that the controller cannot maintain or control idle speed as expected.
An idle-air valve, electronic throttle, vacuum leak, wiring problem, contamination, or incorrect learned values may be involved.
01 // COMMON SYMPTOMS
What you may notice
02 // COMMON CAUSES
What can trigger P0505?
Idle-control valve fault
The valve may stick or fail electrically.
Vacuum leak
Unmetered air can make idle control difficult.
Throttle-body contamination
Deposits may alter expected airflow.
03 // DRIVEABILITY
Can I keep driving with P0505?
The vehicle may remain driveable depending on the symptoms. Diagnose the fault soon, especially if performance, fuel economy, starting, shifting, or engine operation has changed.
04 // DIAGNOSTIC ORDER
Start here
Inspect for vacuum leaks
Check intake and PCV plumbing.
Inspect the throttle or idle valve
Check for sticking or contamination.
Review idle-control data
Compare commanded and actual idle behavior.
Perform relearn if required
Complete manufacturer idle or throttle relearn procedures after repairs.
05 // COMMON REPAIR AREAS
Systems commonly involved
These are common areas associated with P0505. Testing should confirm the actual fault before parts are replaced.
Idle-control valve fault
The valve may stick or fail electrically.
Vacuum leak
Unmetered air can make idle control difficult.
Throttle-body contamination
Deposits may alter expected airflow.
06 // DIAGNOSTIC PRINCIPLE
Confirm the fault before replacing parts
P0505 identifies a condition detected by the vehicle control system. It does not automatically identify one failed component. Test the affected system before replacing parts.
07 // RELATED TORQDEX DIAGNOSTICS
Related diagnostic guides
Continue troubleshooting by symptom and system. These TorqDex guides cover common diagnostic paths associated with this trouble code.
08 // RELATED CODES