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BMW m50 wont start

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We have a 1992 bmw 525i (m50 non vanos motor) in the shop that we have built. We had the car running on the factory ecu before we began installing this one. We are using an e36 plug/play ecu to run our non vanos motor. 

All the pins have been moved around to the correct spot.

Trigger 1 vr crankshaft
Trigger 2 VR camshaft (we used the original m50nv camshaft sensor, it is a vr, the e36 is a hall effect)

All 6 injectors tested ok
All 6 coils tested ok
Coolant temp ok
IAT sensor ok

Cranking RPM is 200 rpm in the link ecu
Trigger 1 and Trigger 2 show NO error

I have tried using 84, 276, -84, -276 as a trigger offset for trying to get this to fire up.

I have had someback fires and "almost" starts.

Need help on what settings to use for the trigger.


Please keep in mind this is obdI e34 m50 non vanos motor. The crankshaft pulley that is on the motor, is still an original one.

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You will need to wire some igniters in, standard Ecu has them built in, your effectively getting a weak spark. Your ignition timing should be -84 degrees providing your crank sensor wiring polarity is correct, if it's not then it will run on 276 but you will end up with trigger and rpm errors. Will put some links up to the igniters and plugs I used 

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Hi, as per the message I sent you

I'm afraid  if you are using the m50 coils you will definitely need external ignitors. I went through all this my self a few months ago. If you look on the link below at the bottom it lists the ignitors as an extra, doesn't say there built in.


 You will need two of these


and again two of these


and to wire them like this


It would be a good idea to post a scope of your tirggers and what map you are using too. And as Adanw says ignition timing will need to be checked with a timing light, I brought this one and it worked a treat


Hope this helps

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I have problem with the m50 engine

good stable crank sensor reading , but when enable the cam , the rpm go random erratic

using stock non vanos vr cam sensor , setup is reluctor , cam pulse x1

any idea?? 


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are you using the vanos crank wheel then? Your cam pulse doesn't line up with you missing tooth gap on the crank wheel like mine does, thinking you might have the wrong crank wheel on? Have you zeroed in your ignition timing using a timing light?

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i use vanos bottom end with the stock vanos crank wheel, yes i notice there r gap with the nv cam sync

i swapped the cam wires, it read well, i use -325 calibrate, but i have feeling the car advances more than the table

i have timing light but i don't know where is the timing mark in the m50s engines

thanx for support

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