P0084
UniversalExhaust Valve Control Circuit/Open (Bank 2)
Medium SeverityThe engine computer detects an electrical problem in the circuit that controls the exhaust valve timing for one side of the engine (Bank 2). This issue can prevent the exhaust camshaft from adjusting properly, leading to reduced engine performance and fuel efficiency.
⚠️ Before You Begin (Safety First)
Always disconnect the battery before working on electrical components. Allow the engine to cool before working on hot components to prevent burns. Be cautious when handling engine fluids.
Common Symptoms
- Check Engine Light illuminated
- Reduced engine power
- Rough idle
- Increased fuel consumption
- Engine may run poorly at certain RPMs
Common Causes
- Faulty exhaust valve control solenoid (VVT/VVTL solenoid) on Bank 2
- Open or short in the wiring harness to the exhaust valve control solenoid
- Poor electrical connection at the solenoid connector
- Low or dirty engine oil (VVT systems rely on oil pressure)
- Faulty Engine Control Module (ECM/PCM) (less common)
Frequently reported on: Honda Pilot 2008-2015, Nissan Murano 2007-2014, Toyota Sienna 2007-2016, Chevrolet Traverse 2009-2017
Diagnostic Steps
- Retrieve and verify the P0084 code using an OBD-II scanner.
- Inspect the wiring harness and electrical connector for the exhaust valve control solenoid on Bank 2 for any signs of damage, corrosion, or loose connections. Repair as necessary.
- Check engine oil level and condition. Low or dirty oil can affect VVT system operation. Change oil and filter if needed.
- Test the resistance of the exhaust valve control solenoid on Bank 2 using a multimeter. Compare reading to manufacturer specifications. Replace the solenoid if it's out of specification.
- If possible, apply direct battery voltage to the solenoid (briefly) to check for an audible click, indicating it's actuating. (Exercise caution to avoid over-energizing or short circuits).
- Clear the code and test drive the vehicle to see if the code returns.
👨🔧 When to Call a Professional
If, after inspecting wiring and attempting to clear the code, the issue persists, or if you suspect internal engine damage related to incorrect valve timing, it's best to consult a professional mechanic. Complex VVT system diagnostics or internal engine work require specialized tools and expertise.
Commonly Asked Questions
What does Bank 2 mean for P0084?
Bank 2 refers to the cylinder bank that does not contain cylinder number one. On most V6 or V8 engines, this specifies which side of the engine the faulty exhaust valve control circuit is located.
Can I drive with a P0084 code?
While you might be able to drive, it's not recommended for extended periods. The vehicle may experience reduced performance, lower fuel economy, and potentially increase emissions. It's best to diagnose and repair it promptly to prevent further issues.
How do I locate the exhaust valve control solenoid on Bank 2?
The exhaust valve control solenoid is usually located on the cylinder head, near the exhaust camshaft on Bank 2. Consult your vehicle's service manual or an online diagram for its precise location.
Does low oil cause P0084?
Yes, variable valve timing systems often rely on engine oil pressure to operate the solenoids and adjust camshafts. Low or dirty engine oil can impede their function, potentially triggering codes like P0084.
Is P0084 an expensive repair?
The cost can vary. Replacing a faulty solenoid itself is often a moderate repair. However, if the issue is a complex wiring problem or points to internal engine damage, the cost could be significantly higher. DIY replacement of the solenoid is usually more affordable.