📋 What P0507 Means
P0507 sets when actual idle RPM holds 100+ RPM above the target idle the ECU is commanding for several seconds. The most common reason is unmetered air entering the engine - a vacuum leak - which makes the engine run leaner and faster than the ECU intends. On older cars, a stuck-open IAC valve has the same effect.
Common symptoms drivers report
- Idle "hangs" high after you let off the throttle
- Idle higher than normal at warm idle (>900 RPM is suspicious)
- Hissing sound under the hood at idle (vacuum leak)
- Rough idle that smooths out at higher RPM
- Lean codes (P0171, P0174) often appear alongside
Safe to drive?Yes, short-term. But a vacuum leak that's causing P0507 will eventually cause misfires and lean operation that hurts the catalytic converter - fix within a week or two.
🎯 Top Causes & Probability
Across all vehicles reporting P0507, these are the most common root causes. Ranking shifts by year/make/model - get a vehicle-specific ranking for $5.99.
#1 · Most likely
Vacuum leak (intake, PCV, hoses, brake booster)
Cracked or disconnected vacuum hoses, a leaking intake manifold gasket, or a torn PCV diaphragm let unmetered air into the engine. The ECU adds fuel to compensate, but idle still climbs.
60%
Parts
$10–$120
Labor
$60–$300
DIY
Medium
#2 · Check second
Dirty or stuck-open throttle body
Carbon buildup can prevent the throttle plate from fully closing at idle. Also seen on drive-by-wire systems where the throttle motor lags or the ECU has a stale idle relearn.
25%
Parts
$8–$15
Labor
$0
DIY
Easy
#3 · Older cars
Stuck or failing IAC valve
On pre-2007 cars with cable throttles, an IAC valve that sticks open commands too much idle air, raising RPM. Cleaning sometimes works; otherwise replace.
15%
Parts
$40–$150
Labor
$0–$120
DIY
Easy
🚗 Most Affected Vehicles
| Vehicle | Frequency | Typical Cause | Mileage |
|---|---|---|---|
| Ford F-150 / Mustang 4.6L–5.4L (2004–2010) | Very High | Intake manifold gasket leak | 80k+ mi |
| Toyota Camry / RAV4 (2007–2017) | High | PCV hose / valve cover gasket | 90k+ mi |
| GM 5.3L Silverado / Tahoe (2007–2014) | High | Throttle body relearn after cleaning | 60k+ mi |
| Honda Accord / Odyssey (2003–2010) | Moderate | IAC valve sticking | 100k+ mi |
| BMW N52 / N54 (2006–2013) | Moderate | Cracked CCV / valve cover | 70k+ mi |
🔧 Step-by-Step Diagnosis
- Listen for hissing under the hoodWith the engine idling, pop the hood and listen carefully. A vacuum leak often gives itself away with a faint hiss near the intake or PCV system.
- Spray-test for vacuum leaksEngine idling, spray short bursts of carb cleaner or propane around intake manifold, PCV hose, brake booster line, and throttle body base. RPM change = leak found.
- Inspect PCV systemThe PCV valve and its hose are the #1 vacuum leak source on older cars. Pull the hose, shake the valve - should rattle. Replace both for $20 if there's any doubt.
- Check intake manifold gasketOn Ford modular V8s and many GM V6s, the intake gasket fails after 80k. A leak there causes both P0507 and lean codes. Replacement is a half-day job.
- Clean throttle body and perform idle relearnAfter confirming no vacuum leak, clean the throttle body and run the manufacturer's idle relearn procedure. On many cars: disconnect battery 10 min, reconnect, idle in park 10 min A/C off then 10 min A/C on.
- Replace IAC valve (cable-throttle cars)On older cars, if cleaning the IAC doesn't fix idle hang, replace it. 15-minute bolt-on job.
💡 Skip the guessworkFor your exact year/make/model, AmpAuto pulls TSBs, OEM torque specs, and live-data targets so you fix it the first time. Run vehicle-specific diagnosis →
🔗 Related Guides
❓ Frequently Asked Questions
What does it mean if my idle stays at 1500 RPM warm?
Anything 200+ RPM above your car's spec means the ECU has lost idle control. P0507 is the typical code. Start with a vacuum leak inspection.
Can a dirty MAF cause P0507?
Indirectly, yes. A MAF reading low makes the ECU underestimate airflow, run lean, and command higher idle to compensate. Clean the MAF with MAF cleaner.
Why did P0507 come right after I cleaned my throttle body?
You cleaned past the carbon "stop" the ECU was using as the idle reference. Run the idle relearn for your make - disconnect battery 10 min, then idle 10 min A/C off, 10 min on.
Will P0507 hurt my engine?
Not directly, but the underlying lean condition can cause misfires that damage the catalytic converter over months. Fix it within a few weeks.
Difference between P0506 and P0507?
P0506 = idle too low (often dirty throttle body or weak IAC). P0507 = idle too high (almost always a vacuum leak).
Can a bad battery cause P0507?
Sometimes. A weak battery or low voltage at the throttle motor can throw idle control errors that mimic P0507. Load-test the battery if it's over 4 years old.