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P0478 Engine Trouble Code

P0478 Engine

When you check engine light came on code P0478 the reason should be Engine Light ON (or Service Engine Soon Warning Light). However your vehicle's manufacturer may have a different definition for the P0478 OBD-II Diagnostic Powertrain (P) Trouble Code. So you should chech it on our car models.

P0478 if your catalytic convertor fails completely, you eventually won't be able to keep the car running. Your gas mileage will also be terrible, so you should try and fix it as soon as you can. Unfortunately, the average replacement cost is around $2,000 and you can't do it yourself unless you're an experienced mechanic.

P0478 Code Meaning :

P 0 4 7 8
OBD-II Diagnostic Powertrain (P) Trouble Code For Engine Intake Valve Control Solenoid Circuit Low Fuel Temperature Sensor B Circuit Range/Performance Injection lump Fuel Metering Control 'B' High (Cam/Rotor/Injector) Timing Reference High Resolution Signal A Too Many Pulses

Is the fuel pump sometimes not priming when you turn the key to ON(II)? Start by measuring the fuel pressure and checking whether you have bright white-bluish spark at all four plugs. The mechanical timing is also something that you should check, as we mentioned above.

P0478 OBD-II Diagnostic Powertrain (P) Trouble Code Description

P0478 OBD-II Trouble Code Exhaust Back Pressure Regulator - Is a variable position valve that controls exhaust back pressure during cold ambient temperatures to increase cab heat and decrease the amount of time needed to defro P0478 code.

Reason For P0478 Code

The reason of P0478 OBD-II Engine Trouble Code is Fuel Temperature Sensor B Circuit Range/Performance.

P0478 DTC specifically refers to the camshaft (cam) timing. In this case, if the cam timing is over-retarded, the engine light will be illluminated and the code will be set.