P12EF
Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 1
P12EF is an OBD-II diagnostic trouble code meaning: Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 1. Common causes: mechanical valve wear, valve contamination by deposits. Estimated repair cost: $28–89.
Symptoms
- Increased fuel consumption
- Reduced engine power
- Uneven engine operation
- Check Engine Light Illuminates
- Problems with acceleration dynamics
Causes
- Mechanical valve wear
- Valve contamination by deposits
- Problems with wiring to the valve
- Control solenoid malfunction
- Control unit software error
How to Fix
- Valve condition diagnostics
- Cleaning or replacing the valve
- Checking the electrical control circuit
- Checking the operation of the solenoid
- Updating the ECU firmware if necessary
Related codes
FAQ
What does the P12EF code mean?
P12EF is an OBD-II diagnostic trouble code that indicates: Cylinder Deactivation Exhaust Flow Valve Stuck Closed Bank 1
What causes a P12EF error code?
The most common causes of P12EF include: Mechanical valve wear; Valve contamination by deposits; Problems with wiring to the valve; Control solenoid malfunction.
How do I fix a P12EF diagnostic trouble code?
To fix P12EF: Valve condition diagnostics. Cleaning or replacing the valve. Checking the electrical control circuit. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with P12EF?
Yes, but get it checked soon
How much does it cost to fix P12EF?
The estimated repair cost for P12EF is $28–89. Actual cost depends on your vehicle, location, and labor rates.
See also: Russian version · NationStat