Idle speed higher than expected on BMW — vacuum leak from CCV/PCV cracked hoses or DISA flap on N42/N46 and N55.
BMW P0507 — Idle speed higher than expected on BMW — vacuum leak from CCV/PCV cracked hoses or DISA flap on N42/N46 and N55. Typical UK independent garage cost: £90–£320.
What actually causes P0507 on a BMW
BMW P0507 is overwhelmingly a vacuum leak — cracked CCV (crankcase vent) diaphragm on N42/N46/N52, split bellow on N55, or the DISA intake-flap O-rings. Easy to find with a smoke test, easy to fix.
BMW engines that log P0507
- N42/N46 2.0 (E46/E90)
- N52/N53 inline-6
- N55 3.0 TwinPower
How we diagnose P0507 on a BMW
- Smoke-test intake from throttle to rocker cover
- Listen at the oil filler cap — strong suction = CCV diaphragm failed
- Inspect DISA flap for play and worn O-rings
- Replace CCV (cold-climate kit on N52 if applicable)
The common misdiagnosis to avoid
Don't replace the throttle body — BMW electronic throttles rarely fail. Smoke-test the vacuum system first; the CCV is the usual suspect.
BMW P0507 repair cost in the UK
Expect £90–£320 including parts and labour at an independent garage. Main-dealer quotes on BMW are usually higher for the same job, and the spread exists because the cheap cause and the expensive cause throw the same code — pay for the diagnosis before you pay for parts.
Bob's workshop tip
N52 P0507 with whistling from the engine bay = CCV. Order the cold-climate kit if the car lives in Scotland.
Codes usually seen alongside P0507 on BMW
- P0171
- P0174
- P1004
Symptoms drivers report with P0507
- The car feels like it's 'creeping' forward too fast at traffic lights without touching the gas.
- Engine revs stay hung up at 1200rpm when you dip the clutch approaching an intersection.
- A noticeable 'hissing' or whistling noise from the engine bay when idling on the driveway.
- The stop-start system has stopped working because the idle isn't stable enough for the ECU.
- Surging or 'hunting' revs when you first start it from cold in the morning.
Repairs that clear P0507
- Smoke-test intake
- Clean throttle body
- Replace PCV valve / rocker cover
- Inspect all vacuum hoses
For the generic, all-makes explanation of this code — meaning, every known cause and UK cost bands — see our P0507 guide.