C3697 Diagnostic Trouble Code

C3697 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 C3697 diagnostic trouble code may include:

Poor acceleration
Cherry red hot catalytic converter
Possible spark knock (detonation / pre-ignition)
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.

Possible Causes :

An air leak forward of the DPF will change the sensor readings resulting in the code
Rusty exhaust systems, cracked exhaust manifolds or damaged or missing gaskets or donuts will cause air leaks.
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.

Repair Processes :

If the scan tool has that capability, and the scan tool can operate the IMRC valves, then the problem is either resolved and a simple code clearing is all that's left or a new PCM would be called for. 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. Oxygen sensors signal the engine management computer the amount of oxygen present in the exhaust, which is used in determining and controlling the fuel ratio.

Process Tips

Diagnostic trouble code C3697 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 C3697.

Fortunately, C3697 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

C3697 Trouble Code For Specific Cars

C3697 Daewoo Nexia Gear 1 Incorrect ratio
C3697 Napier 40 Camshaft Position Sensor Circuit Range/Performance
C3697 Porsche 965 Fuel level Sensor Circuit High Input
C3697 Peugeot Promethee Engine Coolant Temperature Circuit Intermittent
C3697 Cadillac Imaj Decklid Release Circuit Short To Ground
C3697 Bugatti Type 13 Cylinder #7 High To Low Side Open
C3697 Citroen Bx Front Fog Lamp Relay Ckt Short to Battery