P0519Idle Air Control System Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P0519 means the idle control fails functionally with an electrically sound circuit – the actual idle speed deviates strongly despite fully used control. It is documented only on Subaru (also in the Saab 9-2X, electronic throttle, around 2005): idle at least 1000 rpm above target with the control already at zero for 2 or 5 s sets the code with the warning lamp at once, and a fail-safe cuts fuel to cylinders to stop the engine racing. GM and Ford use P0506/P0507 instead; CARB's mandatory limit is +200/−100 rpm.
- What you may notice
- Idle far above target, engine races
- Jerking from cylinder cut-off in limp mode
- Check engine light on
- Likely causes
- LikelyFalse air behind the throttle (intake, gasket, vacuum hose)
- LikelyThrottle or idle valve stuck open (foreign body, coking)
- PossibleThrottle actuator motor faulty (follow-on P2101)
- PossibleFollow-on fault of other codes (sensors, pedal)
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €450
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.