Engine

P0086 — Exhaust Valve Control Solenoid Circuit High (Bank 2)

Severity: medium Drive with care, to a shop

What P0086 means

The engine computer controls a solenoid that directs oil to the variable valve timing mechanism for the exhaust valves on bank 2. P0086 sets when the voltage in that solenoid circuit is higher than expected. This can come from a short to voltage, a wiring or connector fault, or a failed solenoid.

Symptoms

  • Check Engine Light on
  • Reduced engine power
  • Rough or unstable idle
  • Sluggish acceleration
  • Worse fuel economy
  • Possible limp mode

Possible causes

  1. Faulty Bank 2 exhaust valve control solenoid
  2. Damaged wiring: short to voltage, open circuit, chafed insulation
  3. Corroded or loose connector, poor electrical contact
  4. Wrong oil viscosity or low oil pressure
  5. Internal ECM/PCM fault (rare)

How to diagnose

  1. Scan for all codes and freeze frame data, then clear the code and see if it returns.
  2. Check oil level and condition, and confirm the oil matches the specified viscosity.
  3. Inspect the Bank 2 solenoid connector and harness for chafing, oil, corrosion, or heat damage.
  4. Measure supply voltage and the control signal at the connector with a multimeter or scope.
  5. Measure solenoid coil resistance and compare it with the service manual spec.
  6. Test the control wire for a short to voltage and for an open circuit using the wiring diagram.
  7. Command the solenoid with a scan tool active test and watch the valve timing response.
  8. If wiring and solenoid test good, check the ECM and look for a software update.

Common fixes

  • Replace the Bank 2 exhaust valve control solenoid
  • Repair or replace damaged wiring and connectors
  • Clean and secure the electrical connections
  • Change the oil and filter to the correct specification
  • Reflash or replace the ECM (last resort)

Questions and answers

What does P0086 mean?

The ECM detected too high a voltage in the circuit of the solenoid that controls exhaust valve timing on bank 2. The solenoid or its wiring is the most common culprit.

Can I drive with P0086?

For a short time, usually yes, but the engine may run rough and lose power. Diagnose it soon to avoid wasted fuel and higher emissions.

Can bad oil cause P0086?

Wrong viscosity, low level, or dirty oil can affect the valve timing system. Since this code points to high circuit voltage, though, start with the wiring and solenoid before the oil.

This is general information about the code. The meaning can differ between makes and models: a scan tool and the repair manual for your car will show the exact cause.