Cylinder 7 Exhaust Valve Control Circuit Low
The P3455 code indicates that the powertrain control module (PCM) has detected a low voltage condition in the exhaust valve control circuit for cylinder 7. This circuit is part of the variable valve timing (VVT) or cylinder deactivation system, which uses oil pressure to actuate the exhaust valve. A low voltage signal suggests a short to ground, open circuit, or faulty component in the solenoid or wiring. This can cause the exhaust valve to remain closed or operate incorrectly, leading to reduced engine performance, misfires, and increased emissions.
01. Most Common Causes
- Faulty exhaust valve control solenoid on cylinder 7
- Short to ground or open circuit in the wiring harness
- Corroded or damaged connector at the solenoid
- Engine oil sludge or debris blocking the solenoid oil passages
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine misfire or rough idle
- Reduced engine power and fuel economy
- Possible engine knocking or hesitation
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm P3455 and check for related codes.
Step 2: Visually inspect the wiring and connector for cylinder 7 exhaust valve control solenoid for damage, corrosion, or loose pins.
Step 3: Measure resistance of the solenoid; compare to manufacturer specs (typically 10-30 ohms).
Step 4: Check for voltage at the solenoid connector with key on; should be battery voltage. If low, test circuit for shorts or opens.
Step 5: If wiring and solenoid are good, test PCM output by commanding the solenoid on/off with a scan tool.
04. Commonly Affected Makes
05. 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. Short trips to a repair shop are acceptable.
How much does it cost to fix?▼
The cost typically ranges from $200 to $600, including diagnostic time and parts. The solenoid itself costs $50-$150, plus labor for replacement and possible wiring repair.