M5 won't Start... only code is Peake Table 18 #10 CrankShaft Sensor!!

LeatherMan · 20th April 2006, 04:23

As some of you know I just finished a waterpump, thermostat, tempurature sensor, belts, etc. I finally finished the job on Saturday. The battery was too dead to turn over so I put it on the charger. I started the car the next day Sunday and took it for a drive. It seemed to be running great... the engine and oil temp were sitting lower than they have since I bought the car. However, on 3 occasions when I was slowing for a stop light the engine would just shut off on its own. I immediately restarted the engine the first two times and kept driving. On the 3rd time the engine shut off it would not start up again. I towed the car back to the house and pulled the codes. The only code was an

1. engine misfire on empty tank
2. crankshaft sensor

Since I could smell fuel when I turned the car over I assumed the issue had to be spark specifically related to the crankshaft sensor. I bought a sensor from the dealer and replaced it tonight. The beast still won't start. Does anyone have any insight into what could be the problem?

Thanks,
Eric

Beamer_usa · 20th April 2006, 05:40

Sounds electrical, maybe something to do with the security system. The security system does have some type of ignition kill? Good Luck - keep us posted!

LeatherMan · 20th April 2006, 17:00

I have an interesting update on the situation. I did not mention this before, but I had a heck of a time getting the crankshaft sensor out of the bell housing. I ended up breaking it off leaving half of it inside the hole. When I finally got some needle nose vice grips on the remainder of the sensor and pulled it out I noticed that the sensor had a significant gash in it. I have no idea what caused the gash as the new sensor is not even being touched by the flywheel teeth. Both M5dctr and LSCman PMed me and they think that there is something in my bell housing that must have gotten smashed between the flywheel and the sensor causing the gash. I am thinking that they are correct as there is no other explanation for the damage.

I am going to try to inspect the flywheel teeth tonight as I have someone turn the motor over by hand for me. Does anyone else have any insightful ideas about what could have happened?

Regards,
Eric

emccallum · 20th April 2006, 19:27

Quote:

Originally Posted by LeatherMan

I have an interesting update on the situation. I did not mention this before, but I had a heck of a time getting the crankshaft sensor out of the bell housing. I ended up breaking it off leaving half of it inside the hole. When I finally got some needle nose vice grips on the remainder of the sensor and pulled it out I noticed that the sensor had a significant gash in it. I have no idea what caused the gash as the new sensor is not even being touched by the flywheel teeth. Both M5dctr and LSCman PMed me and they think that there is something in my bell housing that must have gotten smashed between the flywheel and the sensor causing the gash. I am thinking that they are correct as there is no other explanation for the damage.

I am going to try to inspect the flywheel teeth tonight as I have someone turn the motor over by hand for me. Does anyone else have any insightful ideas about what could have happened?

Regards,
Eric

As I understand the sensor has a very very close tolerance to the flywheel. A thin spacer can be required to get it into spec, check the Tis for the value. This may be why you cant get it to start after replacing it. perhaps the old one came apart somehow and made contact with the teeth...or (not sure if it is possible)the flywheel is moving due to a failing dual mass mechanism. Keep us posted. Has the clutch been replaced? maybe it was damaged during R&R of the tranny.

LeatherMan · 20th April 2006, 19:51

More interesting/disheartening news... I just did a visual inspection of the flywheel teeth. I had to turn the motor by hand and shine a flashlight in the crankshaft sensor hole. There were very minor scraps on about 15 teeth. There two teeth in particular that had huge gouges in them. The lips of these teeth were also bent in somewhat! My only guess is that a bolt, probably a pressure plate bolt, has broken off and is tumbling around in my bell housing.

I guess it is drop the tranny time... again! I am starting to dislike this car.

I don't think I mentioned this, but I have a SPEC stage III clutch with the aluminum flywheel. I bought the clutch and flywheel setup June of 2005. Other than the uber annoying flywheel rollover noise it has been worked out great. What do you guys think the chances are of Daniel at Beastpower or the people at SPEC will help me out on this? Is the flywheel tooth gear replacable or repairable?

Thanks,
Eric

emccallum · 20th April 2006, 20:57

I don't think I mentioned this, but I have a SPEC stage III clutch with the aluminum flywheel. I bought the clutch and flywheel setup June of 2005. Other than the uber annoying flywheel rollover noise it has been worked out great. What do you guys think the chances are of Daniel at Beastpower or the people at SPEC will help me out on this? Is the flywheel tooth gear replacable or repairable?

Thanks,
Eric[/quote]

AHHH the joys of "upgrading"! As we dig we get the whole story. Did you reuse the flywheel bolts or use new ones? i heard somewhere that they are single use. Anyone else heard of this. When you remove the tranny be sure and check your starter gear for damage.

Reminds me of the time my 84 323 (euro) clutch slave cylinder rod fell into the tranny b/c the pedal stop broke. Every now and then I would hear it rattle around, a few times it made some serious noise. Then one day nothing. Never made another sound for years. Sold it with over 200k on it, never having to go get the rod! Yes, i told the buyer about it.

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LeatherMan · 20th April 2006, 21:52

You actually can't reuse the factory flywheel bolts... they are perminantly encased in the factory Dual Mass Flywheel assembly. The new flywheel comes with new bolts...

Am I screwed?

Eric

emccallum · 20th April 2006, 22:06

i think you will be a ble to tell how screwed you are after you remove the tranny and find the cause of the bad teeth. And it aint gonna be too much sugar...hehe dental joke.