P052E is a function fault of the crankcase ventilation pressure regulating valve. Audi's 3.0 TFSI has a diaphragm valve whose torn diaphragm or elbow causes false air and whistling; Mercedes' M270/M274 have a switched part-load ventilation valve that blocks with oil carbon and lets oil into the intake – blue smoke, rough running, lack of power; Mercedes extended the emission warranty on the intake module. GM Europe's 2.0 diesel in the Saab 9-5 uses P052E differently, for PCV heater performance – which J2012 lists as P053D.
Medium severity. Can I keep driving?If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
Symptoms
- Check engine light on
- Whistling or hissing in the engine bay
- Rough idle, blue smoke or oil consumption, lack of power
Most likely causes
- Diaphragm of the regulating valve torn or fatigued
- Part-load ventilation valve blocked (oil carbon, sludge)
- Elbow or hose at the valve cracked, clamp leaking
- Engine module software
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: hard
- It affects emissions.
What each character of P052E means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 5: Speed and idle
- 2E: Specific fault in that system
Frequently asked questions
Can I keep driving with code P052E?
If the car is running normally, drive in moderation to a repair shop. If it loses power or another warning appears, do not continue.
What causes code P052E?
The most common causes are: diaphragm of the regulating valve torn or fatigued; part-load ventilation valve blocked (oil carbon, sludge); elbow or hose at the valve cracked, clamp leaking.
Related codes
- P051FPCV Filter Restriction
- P053ECrankcase Pressure Too High
- P04DBCrankcase Ventilation System Disconnected
- P04FCCrankcase Ventilation System Performance
- P051BCrankcase Pressure Sensor A Circuit Range/Performance
- P0171System Too Lean Bank 1
Sources
- static.nhtsa.gov: MC 10177763 0001
- static.nhtsa.gov: MC 10193031 0001
- static.nhtsa.gov: MC 10253722 0001
- static.nhtsa.gov: MC 10167492 9999
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.