C1377 Diagnostic Trouble Code

C1377 is a kind of OBD-II Diagnostic C-Chassis Diagnostic Trouble Code.

It is considered generic because it applies to all makes and models of vehicles, although specific repair steps may be different depending on your car model.

Symptoms

Symptoms of a C1377 diagnostic trouble code may include:

Faulty O2 Sensor
Lack of power
If the DPF is not cleared the ECU will revert to the "Limp Home Mode" until the situation is corrected
Rich or lean exhaust

Possible Causes :

Faulty IMRC actuator relay (if equipped)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.
Fuel with a large percentage of sulfur will clog the DPF quickly

Repair Processes :

You might continue by connecting the scanner to the vehicle diagnostic connector and retrieving all stored codes and freeze frame data. With the valve disconnected, the red voltmeter lead should be attached to the IMRC valve power wire and the black voltmeter lead connected to ground. Look at the plug wires to make sure they are not burnt or laying on the exhaust.

Process Tips

Diagnostic trouble code C1377 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 C1377.

Fortunately, C1377 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C1377 Trouble Code For Specific Cars

C1377 Lancia Alpha Speed Wheel RF Input Signal Missing
C1377 Packard Mayfair Driver Door Ajar Circuit Short To Ground
C1377 Sunbeam-talbot 90 Mass or Volume Air flow Circuit Range/Performance Problem
C1377 Porsche 718 Front Sounder Circuit Short to Vbatt
C1377 Mercedes E 300 ABS Pump Switch Circuit Failure
C1377 Fiat Croma Lamp Keypad Output Open Circuit
C1377 Acura Tlx ABS Inlet Valve Coil Rear Circuit Open