Cylinder 4 Deactivation/Intake Valve Control Circuit Performance
The P3426 code indicates a performance issue in the cylinder deactivation system for cylinder 4, specifically related to the intake valve control circuit. This system, often found in engines with Active Fuel Management (AFM) or Displacement on Demand (DoD), uses solenoids to disable valve lift when cylinders are deactivated to improve fuel economy. A performance fault means the circuit is not operating within expected parameters, possibly due to electrical issues, mechanical binding, or oil flow problems.
01. Most Common Causes
- Faulty cylinder deactivation solenoid for cylinder 4
- Wiring or connector issues in the intake valve control circuit
- Low engine oil level or pressure affecting solenoid operation
- Engine control module (ECM) software or hardware failure
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced fuel economy
- Engine misfire or rough idle
- Loss of power or hesitation during acceleration
03. Step-by-Step Diagnosis
Step 1: Scan for additional codes and record freeze frame data.
Step 2: Inspect wiring and connectors for damage, corrosion, or loose connections at the cylinder 4 deactivation solenoid.
Step 3: Test the solenoid resistance and compare to manufacturer specifications.
Step 4: Check engine oil level and condition; perform oil pressure test if necessary.
Step 5: Clear codes and test drive; if code returns, replace the cylinder 4 deactivation solenoid.
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 the issue can cause misfires, reduced fuel economy, and potential engine damage if the cylinder deactivation system malfunctions.
How much does it cost to fix?▼
Diagnosis typically costs $50-$150. Replacing a deactivation solenoid can range from $200-$500 including parts and labor, depending on vehicle make and model.