P0507

00:00What this code means

Code P0507. Idle Control System RPM Higher Than Expected.

In plain English: actual idle speed is staying above the computer's target because extra air is entering the engine, the throttle cannot close correctly, or its learned position is wrong.

A stable high idle may allow a short trip, but it can make the vehicle creep harder in gear and increase stopping effort. Do not keep driving if RPM surges, the throttle sticks, braking feels compromised, or the engine races unpredictably.

00:34How the test actually works

Here's what your engine computer is actually measuring.

At closed pedal, the engine computer targets a specific idle speed using electronic throttle angle or an idle-air-control valve, then trims it with ignition timing and load compensation. It compares that target with actual RPM from the crankshaft signal.

The code sets when actual idle stays above commanded idle by more than the calibrated allowance under valid conditions. The difference and timer are vehicle-specific, and the test may be disabled during warm-up, steering, air-conditioning or charging loads.

So the code is not a part failure report. It's a performance measurement that came back under spec.

01:18Symptoms

What you'll usually notice, beyond the light itself.

Idle speed that stays unusually high. The tachometer may remain well above normal after the engine is fully warm.

Idle surge or hunting. The computer closes airflow and pulls timing while unwanted air keeps pushing RPM back up.

Hard engagement into Drive or Reverse. Selecting a gear at excessive RPM loads the transmission and can make the vehicle jump.

Vehicle creeps more strongly at a stop. Higher engine torque at idle requires more brake pressure than the driver expects.

Code after throttle-body service or battery disconnect. A clean throttle opening can differ from the position stored in the old idle adaptation.

02:07Most likely causes, ranked

Now the part you came for: what actually causes this, ranked by how often it turns out to be the culprit.

32 percent of the time, it's this: Vacuum or intake leak bypassing the throttle. A split hose, manifold seal or brake-booster connection adds air the computer did not command.

23 percent of the time, it's this: Dirty or sticking throttle body or idle-air valve. Deposits can prevent the plate or valve from returning to its intended idle position.

17 percent of the time, it's this: Idle or throttle relearn not completed. Common after cleaning, replacement, battery work or an ECM reset on applications that require a defined learn procedure.

12 percent of the time, it's this: PCV or purge valve stuck open. Either path can become a controlled vacuum leak and feed extra air or vapor at idle.

9 percent of the time, it's this: Throttle cable, stop or plate held open. Check floor-mat interference, cable free play and any recent work; never adjust a factory stop screw casually.

7 percent of the time, it's this: Load-input, charging-system or control-software issue. A false load request or application-specific calibration can make the commanded target itself too high.

Notice that the most expensive repair is not the most likely one. That matters, because the cheap checks come first.

03:39The measurement that decides it

This is the single measurement that tells you whether you need the expensive part or the cheap one.

Warm the engine, turn accessories off as specified, and graph commanded idle RPM with actual RPM. Also watch throttle angle and calculated load so a legitimate load request is not mistaken for a fault.

The commanded line sits near seven hundred RPM, and a healthy actual trace settles onto it after a brief correction. Exact normal speed comes from the service data.

With an air leak, actual RPM stays near twelve hundred even though the target remains normal. After service with an incomplete relearn, RPM may start high and slowly approach the target but never stabilize correctly.

A normal target with high actual RPM points to air bypass, sticking hardware or adaptation. If the target itself is high, diagnose temperature, load requests and input data before touching the throttle.

04:38Diagnostic order

So here is the order to actually test this, cheapest and most likely first.

Step 1. Is actual warm idle high while commanded idle remains normal? Record both values with required loads off. If the computer is commanding the high speed, inspect coolant temperature, charging load, air-conditioning request and other input data first.

Step 2. Are throttle, airflow, lean or intake-leak codes also stored? Save freeze frame before clearing anything. Those companion codes can identify the air path or actuator that explains the high idle.

Step 3. Does an approved smoke test reveal unintended intake airflow? Inspect PCV, purge, booster and manifold branches as well as the main duct. Pinching hoses is only a brief diagnostic check when the manufacturer permits it.

Step 4. Is the throttle or idle-air valve clean, free, and correctly learned? Inspect for deposits and mechanical interference. Clean only by the approved procedure, leave the factory stop screw alone, then perform the exact relearn sequence.

Step 5. Does commanded actuator movement produce the expected RPM change? Use the bidirectional throttle or idle-air test where supported. If the actuator command changes but airflow does not, test the valve or throttle assembly and wiring before replacement.

Target-versus-actual data keeps a relearn or air leak from turning into an unnecessary throttle-body replacement.

06:20Repair costs

What this costs to put right, in US dollars, parts and labor.

Vacuum hose or intake seal: 10 to 100 dollars in parts, plus about 0.7 hours of labor. Often the cheapest repair and the first reason to smoke-test.

Throttle-body cleaning and idle relearn: 10 to 35 dollars in parts, plus about 0.8 hours of labor. Use the factory cleaning and adaptation procedure.

PCV or purge valve: 25 to 180 dollars in parts, plus about 0.8 hours of labor. Prove the path is flowing at idle before replacement.

Idle-air-control valve: 40 to 300 dollars in parts, plus about 0.7 hours of labor. Applies to systems with a separate valve rather than electronic throttle.

Electronic throttle body: 150 to 700 dollars in parts, plus about 1.0 hours of labor. Requires confirmation and often a scan-tool relearn after installation.

P0507 commonly ends with an air leak, cleaning or relearn, not a complete throttle body. Compare target with actual RPM before buying the expensive part.

07:37Recap and related codes

Quick recap. P0507 means actual idle stayed above the computer's target. Confirm the target, save companion codes, smoke-test every bypass path, inspect and relearn the throttle or idle valve, and replace an actuator only after a command test proves it.

If your scan tool showed a related code alongside this one, check those too: P0505, P0506, P0171, P2279.

Codes are on screen and linked below.