2001 M5 Cranks but won't starts!!!! HELP!!! - The Unofficial BMW M5 Messageboard (m5board.com)

rrdaniel · 8th August 2009, 20:59

Hello Everyone-

I am new to this forum but I am hoping that I will get the help needed.

I have a 2001 M5, Recently my clutch started slipping and decided to replace the clutch. I bought an aftermarket clutch SPEC to replace the worn BMW clutch. The mechanic replaced the clutch with no issues and while connecting the exhaust and electrical under the car, he noticed that the crank sensor was cracked so he went ahead and replaced it.

Once he finished, he tried to start the car but it won't start. The car will crank but no spark"ignition" is given and the car won't start.

The car is getting the fuel it needs and I think that the computer blocked or locked the ignition system for the engine to fire.

I believe, He disconnected the battery when he was doing this job or he might have done that when the car wouldn't start in order to reset the computer.

Anyhow, The car is not in another shop getting looked at hoping that All we need to do is re-flash the computer.

I won't know anything until monday, but has this happened to anyone? or any suggestion what might be the issue?

could unplugging the battery cause the computer to lose memory or block the ignition system? What could have happened to cause the car "NOT START"

Please help!!!!!!!

razahyde · 8th August 2009, 21:17

tell him to check the crank position sensor on the transmission and that its plugged in. i forgot to plug mine and my car would crank but not turn on. also double check all the plugs associated with the transmission. that's more then likely your problem.

-R

rrdaniel · 8th August 2009, 21:56

We checked the crank sensor and it is connected just fine. Anything else can I check for?

gregh86 · 9th August 2009, 02:55

Not 100% sure but doesn't the crank sensor have to be set at the correct depth giving a set clearance between sensor and flywheel.

Greg