C2077 Pontiac G5 Diagnostic Trouble Code

C2077 Pontiac G5 code definition:
C2077 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code for Pontiac G5.

C2077 Pontiac G5 or the Evaporative Emission Control System Incorrect Purge Flow is the set whenever the computer sees that there is a problem with the flow coming from the purge valve or the purge flow is not enough within the EVAP system. As you drive and when specific conditions are slowly met, the vapors will gradually purge from the charcoal canister and will get burned within your engine.

Symptoms

Symptoms of a C2077 Pontiac G5 diagnostic trouble code may include:

Poor fuel economy
Possible spark knock (detonation / pre-ignition)
Misfire
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.

Possible Causes :

Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.
A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture.

Common Misdiagnoses

Control Module Throttle Actuator Position Performance Problem
Air Conditioning (A/C) Clutch Feedback Circuit High Voltage Problem
Cruise Vehicle Speed/Set Speed Difference Too High Problem
Kick-Down Switch Failed Short Problem
Park/Neutral Postion (PNP) Switch Circuit Engine Torque Signal Circuit Problem

Repair Processes :

Find out what kind of system you have and verify that voltage to the fuel level sensor is present at the fuel pump wiring harness. Replace the oxygen sensor that is downstream from the catalytic converter on the side of the engine that does not contain cylinder #1. Also, if a oxygen sensor code stating "heater circuit malfunction" the sensor has most probably failed. You might continue by connecting the scanner to the vehicle diagnostic connector and retrieving all stored codes and freeze frame data.

Process Tips

Diagnostic trouble code C2077 Pontiac G5 is not difficult to diagnose and repair. Thus, it always pays to have a qualified technician to look after your vehicle should this error code arise.

Diagnosing this code requires the engine to be in good running shape, without unmetered air entering the engine. If other codes that relates to misfiring condition, lean running or air entering the engine is present, then you must first fix those error codes before C2077 Pontiac G5.

Fortunately, C2077 Pontiac G5 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.