M50 cranks a few times, then stops.

[Blitzer418]

Hi guys!
I'm at a bit of a loss right now because 2 weeks ago my perfectly running M50 engine decided to kick me in the ass. I drove it out to the gas station, drove it back with zero issues. Got in my driveway, tried starting it and the car wouldn't start.
That first time it happened, the engine did crank fine but the exhaust was popping pretty bad (obviously the ignition is wrong), but now it cranks maybe 3 times and stops dead. These are the few things I've done so far,
-battery is fully charged
-replaced ECU
-replaced cam and crank position sensor

and im STILL having zero luck. I know an obvious diagnosis would be to get an obd1 scanner, but right now I'm having trouble locating one that wont require me to bring the car in. Any thoughts or opinions will be greatly appreciated!! Thanks guys!

[Sea Aych]

Do you have a check engine light on? Just do the stomp test (you-tubeable to help get the timing of it right), and the CEL will flash your codes.
Halfway down this page is the table of codes:
http://www.pelicanparts.com/BMW/tech...de_Reading.htm

What else have you checked for?

[dude8383]

It cranks three times and then refuses to restart? Do you hear the starter, if not... What about the solenoid?

[M3PO]

Cranks as in the starter turns the engine over or cranks as in sputters but doesn't start?

[Blitzer418]

OK! I figure a video will help explain whats going on... So take a good look and a listen: https://youtu.be/2WtnCEzG_mY

Unplugging the fuel pump lets the engine crank non stop, its only until the fuel injectors are squirting fuel that the engine stops.

Wow first time I've used the slow-mo feature on the iphone, that worked great!! Showing how it cranks a few times, and actually fires the engine BACKWARDS. Correct me if I'm wrong, but this clearly looks like an ignition timing issue.

Do you have a check engine light on? Just do the stomp test (you-tubeable to help get the timing of it right), and the CEL will flash your codes.
Halfway down this page is the table of codes:
http://www.pelicanparts.com/BMW/tech...de_Reading.htm

What else have you checked for?

Hey Sea Aych! If you remember me at all, or if you noticed in the video, I'm the guy with the Triumph TR6. Unfortunately I'm not sure if the stop test is working for me, as I only have certain things working with the gauge cluster (mainly speedo, temp sensor, and tach). See picture for my janky setup hidden behind the glove box.

[Blitzer418]

Holy crap guys... I literally just figured it out!! The bolts are missing from the timing plate!! Wow this is hilarious, slow motion saved the day. Thoughts? Comments? laughs? Either way I'm glad I know what it is now. Thanks guys!