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.

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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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