P266D Diagnostic Trouble Code

P266D is a kind of OBD-II Diagnostic P-Powertrain 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 P266D diagnostic trouble code may include:

Excessive exhaust leak
Hesitation upon acceleration
Malfunction Indicator Lamp (MIL) illuminated
Diminished fuel efficiency

Possible Causes :

Some aftermarket accessories and performance modifications
A faulty oxygen sensor. This will set a code in itself, however, a faulty oxygen sensor does not automatically condemn the sensor. The code just means that the sensor signal was not within specifications. An air leak or any of the above will cause an erroneous signal. There is a multitude of O2 codes relating to O2 performance which gives a clue to the problematic area.
Low fuel pressure caused by a clogged filter, failing fuel pump, failed fuel pressure regulator or clogged or leaking injectors.

Repair Processes :

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. If you find a related TSB, the information will often help in diagnosing the code in question as TSBs are crested from many thousands of repairs.

Process Tips

Diagnostic trouble code P266D 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 P266D.

Fortunately, P266D is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

P266D Trouble Code For Specific Cars

P266D Fiat Panda Lamp Turn Signal Rear Output Circuit Short To Ground
P266D Audi Q3 ASM Adaptive Learning Not Done
P266D Connaught L2 Fuel Restriction Condition
P266D Honda Hr-v PSD Not Fully Closed (Module Commanded Successfully)
P266D Healey Tickford Passengers Seat Belt Buckle Switch Circuit Short to Battery
P266D Moretti Moretti Blower Switch Failure
P266D Allard J2 Air Bag Diagnostic Monitor Ground Circuit Short To Battery