P186D Diagnostic Trouble Code

P186D 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 P186D 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.

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. Look at the plug wires to make sure they are not burnt or laying on the exhaust. If all testing has passed so far yet you still have the same code, check your scan tool and see if it can open and close the IMRC valve.

Process Tips

Diagnostic trouble code P186D 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 P186D.

Fortunately, P186D is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

P186D Trouble Code For Specific Cars

P186D Boll Limousine Compressor Failure
P186D Simca Vedette Beaulieu Intermediate Speed Sensor (ISS) Malfunction
P186D Vauxhall Agila B Power Window RR Motor Circuit Open
P186D Rover Vitesse Ignition Key-In Circuit Open
P186D Kia Pride Second Fuel Pump Faulty or Ground Fault
P186D American Speedster Air Suspension Height Sensor Power Circuit Short To Ground
P186D Mercedes Gla Accelerometer Rear Circuit Short To Battery