P146B Volvo P1900 Diagnostic Trouble Code

P146B Volvo P1900 code definition:
P146B is a kind of OBD-II Diagnostic P-Powertrain Diagnostic Trouble Code for Volvo P1900.

P146B Volvo P1900 is described as Fuel System Too Rich, which basically means bank 1's oxygen sensor has detected a rich condition of fuel. This means there's not enough oxygen in the exhaust from too much fuel being delivered into the air and gas mixture for combusion. So if the problem persists despite of your diagnosis, then you should never hesitate to take your vehicle to your dealer or to a qualified mechanic.

Symptoms

Symptoms of a P146B Volvo P1900 diagnostic trouble code may include:

Faulty PCM
The light may stay on or light intermittently as the DPF regenerates. The engine will be sluggish on acceleration.
Poor acceleration
Diminished fuel efficiency

Possible Causes :

Faulty IMRC actuator/sensor
A large vacuum leak would cause a massive amount of un-metered air to enter the intake manifold resulting in an overly lean mixture.
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.

Common Misdiagnoses

Vehicle Speed Output Circuit Problem
Cruise Control Servo Indicates Low Problem
A/C System High Pressure High Temperature Problem
PCM Stack Overrun Problem
Transmission Control Module Reprogrammable Memory Problem

Repair Processes :

Now, clear the codes and test-drive the vehicle to see if the code is reset. 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.

Process Tips

Diagnostic trouble code P146B Volvo P1900 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 P146B Volvo P1900.

Fortunately, P146B Volvo P1900 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.