C0170 BMW Fault Code

Description:

The input turbine speed sensor detects rotation of the input shaft of the input shaft speed sensor transmission. The computer uses that information, along with the output shaft speed sensor to determine if the transmission is operating according to plan. If the computer detects a difference between the input shaft speed , and the expected output shaft speed, it will adjust transmission pump pressure to prevent clutch disc slip. If adding pressure doesn't solve the problem, it will set a trouble code.

C0170 Code Symptoms :

The original multi-displacement system turned off opposite pairs of cylinders, allowing the engine to have three different configurations and displacements. C0170 code had an elaborate diagnostics procedure, including showing engine trouble codes on the air conditionning display. However, the system was troublesome, misunderstood by customers, and a rash of unpredictable failures led to the technology being quickly retired.

Diagnosis And Repairing C0170

C0170 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 C0170 code ?

• Damaged VCT phaser
• Continuous oil flow to the VCT piston chamber
• Incorrect Positive Crankcase Ventilation (PCV) hose connection
• Spark plugs may be faulty

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.