P0507 on a Mercedes-Benz: Causes, Fixes & Repair Cost
🟠 Moderate severity · drivable
Drivable, but the engine idles too fast, which wastes fuel and feels unusual at stops.
What P0507 means on a Mercedes-Benz
On a Mercedes-Benz, P0507 means the engine idles faster than the computer expects. Too much air is entering the engine at idle, often through a vacuum leak. The car still drives, but the high idle wastes fuel and feels unusual at stops.
Is P0507 common on Mercedes-Benzs?
P0507 appears on Mercedes models like the C-Class, E-Class, ML-Class, and GLK-Class, most often as vacuum hoses age and crack. Mercedes engines use vacuum for several systems, so even a small leak can raise idle speed. A smoke test is the usual way to find it.
Commonly reported on: C-Class, E-Class, ML-Class, GLK-Class.
Symptoms
- Check engine light is on
- High idle speed
- Engine surges at idle
- Idle stays high when stopped
Common causes
- most common: Vacuum leak from an aged hose
- common: Leaking intake boot or crankcase hose
- less common: Sticking idle control valve
- less common: Dirty or sticky throttle body
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Find and repair vacuum leaks | Yes | $20–150 |
| Clean the throttle body | Yes | $10–40 |
| Have a smoke test done to locate the leak | Mechanic | $50–150 |
Frequently asked questions
Other common Mercedes-Benz codes
P0507 on other brands
Looking for the full (non-brand-specific) guide? See the P0507 code page →
Browse all Mercedes-Benz codes: Mercedes-Benz hub →
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.