Q: car crank not start, 2004 BMW 745i

asked by on August 22, 2016

Hi, I have a 2004 bmw 745i and it recently broken down. I got a fault code P1727. this car can crank but no start. please what this fault code meaning. thanks

My car has 100000 miles.
My car has an automatic transmission.

The code you listed, P1727 indicates that the engine speed sensor is not providing a signal to the computer. Without knowing the position of the crankshaft, the ECM does not know when to inject fuel or when to ignite a spark. Further electrical tests can confirm the sensor is failing. If you need help with testing and repair, a certified technician, like one from YourMechanic, will be able to test the sensor to diagnose the no start and guide you with the next steps.

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