P0077
Intake Valve Control Solenoid Circuit High (Bank 1)
Moderatevariable valve
Overview
The P0077 diagnostic trouble code indicates a intake valve control solenoid circuit high (bank 1) condition. This code relates to the variable valve timing (VVT) system, which adjusts camshaft timing for optimal performance across the engine's RPM range. VVT issues often stem from oil quality or flow problems and can cause rough idle, poor performance, and decreased fuel economy.
Symptoms
- Ticking or clicking noise from engine
- Engine stalling at idle
- Reduced engine performance
- Rough or unstable idle
Common Causes
- Worn timing chain or stretched chain
- Faulty VVT solenoid/actuator (oil control valve)
- Wiring issues in VVT solenoid circuit
- Failed VVT phaser/actuator
Diagnosis Steps
- 1Connect an OBD-II scanner and read all stored trouble codes and freeze frame data
- 2Check engine oil level and condition; change oil if dirty or incorrect viscosity
- 3Test the VVT solenoid (oil control valve) with a multimeter
- 4Inspect the VVT solenoid screen/filter for debris or sludge
- 5Monitor camshaft position sensor data using scan tool live data
Estimated Repair Cost
$150 — $1,000
Cost varies by vehicle, location, and repair shop. Includes parts and labor.
Commonly Affected Vehicles
Toyota Camry (2.5L)Honda Civic (VTEC)BMW 3 Series (VANOS)Ford Escape (EcoBoost)
Related Codes
More Variable Valve Codes
P0008Engine Position System Performance (Bank 1)
SevereP0009Engine Position System Performance (Bank 2)
SevereP0010Intake Camshaft Position Actuator Circuit (Bank 1)
ModerateP0011Intake Camshaft Position Timing Over-Advanced (Bank 1)
ModerateP0012Intake Camshaft Position Timing Over-Retarded (Bank 1)
ModerateP0013Exhaust Camshaft Position Actuator Circuit (Bank 1)
ModerateFrequently Asked Questions
Yes, dirty or low-quality engine oil is one of the leading causes of VVT system problems. Oil sludge can clog the VVT solenoid screen and oil passages, preventing proper cam timing adjustment.