GarageGuideIdle control (RPM higher than expected)
P0507 Code: Idle RPM Higher Than Expected
P0507 stands for "Idle Air Control System RPM Higher Than Expected." When your foot is off the gas, the engine computer tries to hold a specific idle speed, usually somewhere around 600 to 900 rpm once warm. P0507 means the idle is running higher than that target and the computer cannot bring it down.
A high idle almost always means the engine is getting extra air the computer did not plan for. That extra air can sneak in through a vacuum leak, or the part that controls idle air can be dirty or sticking. The code is rarely about a broken computer.
P0507 is not dangerous by itself. A high idle wastes fuel and makes the car creep more when stopped. Keep a firm foot on the brake at stops, and get it looked at so the vacuum leak or sticking part does not get worse.
You can drive normally. Be aware the car may pull forward harder at stops, so keep your foot firmly on the brake. If the idle races very high or the car surges on its own, have it checked before driving further.
Symptoms you might notice
- Check engine light on
- Idle speed noticeably high when warm, often above 1,000 rpm
- Idle that surges up and down
- Car creeps forward more than usual when stopped in Drive
- Sometimes a hissing sound from the engine bay
- Slightly worse fuel economy
Common causes
Vacuum leak
A cracked or disconnected hose, a leaking intake gasket, or a split intake boot lets extra air in, which raises the idle. This is the most common cause.
Dirty throttle body
Carbon buildup around the throttle plate can stop it from closing fully or confuse the computer's idle learning, especially on drive-by-wire engines.
Faulty or dirty idle air control valve
Older engines use an idle air control valve to let air bypass the throttle. When it sticks open, the idle stays high.
Bad PCV valve or hose
A PCV valve stuck open or a cracked PCV hose acts like a vacuum leak.
Idle relearn needed
After a battery disconnect or throttle body cleaning, some cars need to relearn their idle. Until they do, the idle can run high.
Sticking throttle cable or pedal
On cable-operated throttles, a cable that does not return fully holds the throttle slightly open.
Before you buy parts
P0507 almost always means extra air is getting into the engine. Check for vacuum leaks and a dirty throttle body before replacing sensors or the throttle body itself. A cracked hose or a can of throttle body cleaner fixes this code far more often than an expensive part does.
What to check
- With the engine running, listen carefully around the engine for a hissing sound, which points to a vacuum leak.
- Look over the vacuum hoses, the PCV hose, and the large rubber intake boot between the air filter box and the engine for cracks or loose clamps.
- Look inside the throttle body opening (with the engine off and the intake boot removed) for black carbon buildup around the edge of the throttle plate.
- If the battery was recently disconnected or the throttle body cleaned, look up the idle relearn procedure for your car; some need a specific sequence of key-on and idle time.
- A shop can run a smoke test to find vacuum leaks that you cannot see or hear.
Possible repairs
Repair a vacuum leak
Replacing a cracked hose, intake boot, or PCV hose is often inexpensive and fixes the high idle.
Clean the throttle body
Cleaning carbon from the throttle body with throttle body cleaner is a common DIY fix. On drive-by-wire throttles, do not force the plate open by hand with the key on.
Clean or replace the idle air control valve
On engines that have one, cleaning or replacing a sticking idle air control valve restores normal idle.
Replace the PCV valve
A PCV valve is usually an inexpensive part and an easy replacement.
Perform an idle relearn
Following your car's idle relearn steps after cleaning or a battery change lets the computer set the correct idle.
Parts and tools that may help
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Frequently asked questions
Is P0507 serious?
Not usually. It means the idle is higher than it should be, which wastes fuel and makes the car creep at stops. Fix it soon, but it is not an emergency.
Can I drive with P0507?
Yes. Keep a firm foot on the brake at stops because the car may pull forward harder than normal.
Will cleaning the throttle body fix P0507?
Often, yes, if carbon buildup is the cause. Some cars then need an idle relearn procedure to settle the idle back down.
What is the most common cause of P0507?
A vacuum leak, such as a cracked hose or intake boot, followed by a dirty throttle body or idle air control valve.
Why did P0507 appear after I replaced my battery?
Some cars lose their learned idle settings when the battery is disconnected. An idle relearn procedure usually fixes it.