U1656 BMW Fault Code
Check U1656 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.
U1656 Code Symptoms :
![See U1656 in engine](../obd/29.jpg)
The U1656 Check Engine lamp is perhaps the most troubling of lights because it could mean so many different things, from you didn't screw the gas cap on tightly enough to look out for pistons flying through the hood and into the stratosphere. The easiest way to find out what this light is telling you is to hook your vehicle up to a scan tool. U1656 diagnostic tool looks a little like an oversized calculator and plugs into a communication port inside the car. After you instruct it to perform the scan, it speaks with your car's computers to find out exactly what's prompting the light to turn on.
Diagnosis And Repairing U1656
U1656 OBD2 may also be triggered by faults earlier down the line. For example, a dirty MAF sensor might be causing the car to overcompensate in its fuel-trim adjustments. As a result, oxygen sensors are likely to report fuel mixture problems.
How to fix U1656 code ?
- Faulty Air Flow Meter
- Faulty Variable Camshaft Timing (VCT) position solenoid
- Damaged VCT phaser
- Air fuel ratio (A/F) Sensor 1 Bank 1 harness is open or shorted
As the engine heats up and combustion becomes easier and more complete, the PCM will command the idling control valve to increase the amount of air entering the engine to suit the changing conditions.
However, when the load on the engine changes, say, when some electrical consumers or other systems are either turned on or off, the PCM adapts the signal voltage to the idle control valve to ensure that the idling speed remains stable, and at the RPM specified by the manufacturer.