C1398 BMW Fault Code
Check C1398 OBD Fault Code ReasonThe Throttle Position sensor signals the Engine Control Module as to the current position of the engine throttle valve.
The current throttle valve opening is based on the driver's input from the gas pedal.
The ECM uses the information from this sensor to help calculate fuel delivery and spark timing.
C1398 Code Symptoms :
There are currently two main types of cylinder deactivation used today, depending on the type of engine. C1398 code for the pushrod design which uses solenoids to alter the oil pressure delivered to the lifters. In their collapsed state, the lifters are unable to elevate their companion pushrods under the valve rocker arms, resulting in valves that cannot be actuated and remain closed.
Diagnosis And Repairing C1398
C1398 OBD2 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.
How to fix C1398 code ?
- Faulty Air Flow Meter
- Faulty Intake Valve Timing Control Solenoid Valve
- Fuel Injectors circuit poor electrical connection
- Missing or loose fuel cap
Gear changes are accomplished by a command from the BMW TCM to energize the clutch actuator to release the clutch; after which various actuators inside the transmission disengage the current gear, and depending on current operating conditions, engage the next higher or lower gear ratio. All of this happens much faster than a human driver could change gears, and in most applications, gear changes are as smooth and seamless as on any fully automatic transmission.