27BC
High27BC — Exhaust VANOS Control Circuit Malfunction, Bank 2
Description
What the code means
Code 27BC points to a fault in the exhaust VANOS (Variable Camshaft Timing) control circuit on bank 2 (cylinder bank 2). This error is the counterpart to code 27BB, but on the other bank. The VANOS system adjusts camshaft timing to optimize power, fuel economy, and emissions. The code sets when the VANOS solenoid misbehaves, the wiring has a problem, or the DME control unit fails.
Symptoms
Symptoms
- Loss of engine power
- Rough idle
- Check Engine light comes on
- Increased fuel consumption
Causes and fixes
Diagnosis and repair
Step 1: Diagnose with ISTA
Connect the ISTA diagnostic scanner to read codes and check live VANOS values.
Step 2: Inspect the exhaust VANOS solenoid, bank 2
Check the solenoid for contamination or damage. Measure the coil resistance with a multimeter.
Step 3: Replace the solenoid
If it's faulty, replace it with an OEM unit (11367579073).
Step 4: Check oil pressure
Low oil pressure can trigger VANOS errors. Check the oil level and condition, and verify the oil pump is working.
Possible secondary damage
Secondary problems
Ignoring code 27BC can lead to a timing chain jump from the faulty VANOS operation, which can cause serious engine damage (up to and including bent valves). Prompt diagnosis and repair are recommended.