P0077 Engine Trouble Code
What is P0077?
When P0077 code appears, first check your gas cap. Pull over safely, ensure it is tight, and inspect for cracks. A loose or damaged gas cap affects fuel-system pressure and emissions. A replacement cap costs about $3–$10. This simple fix can resolve the code and improve fuel economy.
Code Information
| Code Type: | OBD-II Powertrain (P) Trouble Code |
| System: | Powertrain |
| Code: | P0077 |
P0077 Symptoms
Check Engine Light
Illuminated dashboard warning
Engine Stalling
Engine stops unexpectedly or misfires
Performance Issues
Reduced power or acceleration
Starting Problems
Difficulty starting the engine
P0077 Code Structure
Understanding what each digit means in the P0077 powertrain trouble code:
| P | 0 | 0 | 7 | 7 |
|---|---|---|---|---|
| Powertrain Code | Intake Valve Control Solenoid Circuit Low | Ambient Air Temperature Sensor Circuit Low | Cylinder 10 Contribution/Balance Fault | Shift/Timing Solenoid Malfunction |
How to Fix P0077
Diagnostic Steps:
Oxygen sensors measure exhaust gas oxygen content to optimise air-fuel ratio. This optimisation improves fuel economy and reduces emissions. Sensors degrade over time and require periodic replacement.
Repair Solution:
Firing order is engineered to minimise vibration. Altering firing order results in mistimed ignition and poor engine operation. Consult vehicle-specific repair manual for correct firing order.
Technical Notes:
P0077 on electronically controlled automatic transmissions relates to shift solenoid operation. The solenoid actuates hydraulic circuits controlling clutches or bands for gear changes.
P0077 Description
P0077 OBD-II Trouble Code: Intake Valve Control Solenoid Circuit High Bank 1 is the generic definition for the P0077; however your vehicles manufacturer may have a different definition and information for the P0077 code.
Main Cause
The primary reason for P0077 OBD-II Engine Trouble Code is: Ambient Air Temperature Sensor Circuit Low.