P2903 Diagnostic Trouble Code

P2903 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 P2903 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 :

Rough running engine due to misfiring plugs. Many engines have misfire codes to indicate the cylinder effected, such as P0307 for number 7.
Rarely - faulty Powertrain Control Module (PCM-programming required after replacement)
A large air leak at or near the number one oxygen sensor would also cause a lean mixture.

Repair Processes :

If the engine displays a miss and there wasn't a code, determine which cylinder is misfiring. If the exhaust manifold is visible, spay or pour a small amount of water on each cylinder exhaust port. Water will evaporate immediately on good cylinders and slowly on the missing cylinder. If this can't be accomplished pull the plugs and check the condition. Look for missing ground strap or a rusty ground where the fuel tank is grounded to the frame. Check for damage to the wiring harness connector. Check to make sure they are not burnt or corroded. If in doubt, get some Electrical Contact cleaner at any parts store if cleaning of the terminals is needed.

Process Tips

Diagnostic trouble code P2903 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 P2903.

Fortunately, P2903 is a fairly common OBD code, meaning that it applies to all makes and models of vehicles made after 1996.

P2903 Trouble Code For Specific Cars

P2903 Delahaye Gfa Hydraulic Pressure Sensor Range/Performance
P2903 Lancia Dilambda Speed Wheel Sensor LR Input Short Circuit To Ground
P2903 Vauxhall Calibra Pressure Control Solenoid "A" Short Circuit
P2903 Nissan Fuga Clutch Position Fault
P2903 Bmw R 1200 Gs Clutch position ckt short to battery
P2903 Seat Ibiza Injector Control Pressure Above Expected Level
P2903 Lexus Lf TCM Power Relay Sense Circuit Low