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P128A BMW Fault Code

Check P128A OBD Fault Code Reason
Description:

The Camshaft Position sensor will signal the Engine Control Module when the #1 cylinder is ready for the spark plug to fire (top-dead-center on compression stroke).

The ECM uses the information from this sensor to help calculate fuel delivery and spark timing.

P128A Code Symptoms :

See P128A in engine

The rule of P128A code when it comes to emissions-related vehicle repair is that any modification that changes the vehicle from a certified configuration to a non-certified configuration is considered tampering: this applies to both vehicle owners and repair facilities and is, therefore, a Federal offense. Replacing a catalyst with a straight pipe is one traditional example of P128A.

Likewise, overriding the OBD system through the use of high-tech defeat devices or non-certified computer chips, for example, would also be considered tampering. The OBD system may, however, be repaired back to its original certified configuration with certified performance chips or appropriate aftermarket parts.

Diagnosis And Repairing P128A

Parts or components should not be replaced with reference to only a P128A DTC. The vehicle service manual should be consulted for more information on possible causes of the fault, along with required testing.

How to fix P128A code ?

  • Exhaust gas leaks
  • Continuous oil flow to the VCT piston chamber
  • Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
  • Fuel Injectors circuit poor electrical connection

On some transmissions, such as automated manual transmissions or automatic transmissions with manual mode, the GSP switch lets the TCM know whether or not the driver has selected automatic or manual function.

On manual transmissions, the GSP switch informs the TCM which gear the driver is selecting, and may function as a neutral safety switch, depending on system design. The TCM also uses the gate select position switch to monitor transmission operation. For example, if the driver selects manual mode and selects 3rd gear on an automatic transmission, the TCM may monitor speed sensors to detect clutch and brake slippage.

BMW Cars that meet P128A error