Cylinder 6 Exhaust Valve Control Circuit High
The P3448 code indicates that the powertrain control module (PCM) has detected a high voltage condition in the exhaust valve control circuit for cylinder 6. This circuit controls the variable valve timing or cylinder deactivation system, which adjusts exhaust valve lift. A high voltage reading suggests a short to power, open circuit, or faulty component in the solenoid or wiring.
1. Most Common Causes
- Faulty exhaust valve control solenoid on cylinder 6
- Short to power or open circuit in the wiring harness
- Corroded or damaged connector at the solenoid
- Failed PCM (rare)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Rough idle or misfire on cylinder 6
- Reduced engine power or performance
- Poor fuel economy
3. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect wiring and connector at cylinder 6 exhaust valve solenoid for damage or corrosion.
Step 3: Measure voltage at the solenoid connector with key on; should be battery voltage. If high or no voltage, check circuit.
Step 4: Test solenoid resistance with a multimeter; compare to specs (typically 10-30 ohms). Replace if out of range.
Step 5: Clear code and test drive; if code returns, replace solenoid or repair wiring.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances as it can cause engine misfire, reduced performance, and potential catalytic converter damage.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for DIY repair (solenoid part) or $200-$400 at a shop including labor.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.