DME for 1994 320i E36

[Ross Trilsbeck]

My 320 let out a puff of smoke into the cabin then started running like it lost a cylinder. I brought into the dealer today and they said I blew a spark plug coil. No big deal, however it fried the circuit in my DME for this cylinder. Consequently I am looking for a DME PN Siemens 5WK9.003MS40.1, BMW pn 12-14-1-744-709 (uncoded), 12-14-1-744-959 (coded).
Has anyone had a similar problem. I find it hard to believe that I blew the brain out of my car simply because of a failed coil. Should I be looking at changing out the other coils?
Ross Trilsbeck, Calgary Alberta 403-650-0759
rosstrilsbeck@shaw.ca

[Tim Polzin]

I just had my DME apart for another reason. I did not pay much attention to the coil drivers, but if they are discrete transistors, you might be able to repair the DME.

Tim

[parolof]

the coil must have shorted out and sent thousands of volts into the DME

[Tim Polzin]

Originally posted by parolof
the coil must have shorted out and sent thousands of volts into the DME

Possible, but more likely the coil shorted causing the output transistor to that coil to overload. If the engine is still running on the other 5 cylinders, not too much can be wrong with it.

Tim

[blkongry]

I agree... sounds like you lost a power transistor of some sort. It should be pretty easy to spot... most of them are rough-surface ceramic, and it's probably got carbon discharge on it (I had to change one out on a sputter coater a while back). It should be pretty easy to replace, but I hope you can figure out what the correct replacement is. I highly doubt BMW has a part for their power transistors. Most discrete parts are labeled, so I hope this one is too.