BMW Ignition/Electrical Problem

pugmyre, Jun 12, 6:34am
1980 BMW Coupe 635sci 3.5 litre manual.After start up, it would run for about 10 minutes, it would then just cut out and stop.It has power everywhere, but nothing on the distributor.It's completely dead.Turns over ok.Is there a cut out system on these cars!

pugmyre, Jun 12, 9:03am
Hi bob.Electronic on this one.Cheers.

richard198, Jun 12, 12:42pm
If this has only happened once (start, run for 10 then stop) then your pulse coil may have decided to fail having tried for all of 10 minutes! Can you get a ohmeter on the coil!

elect70, Jun 12, 11:59pm
Do the resistors get hot if so then coil is ok, they do tend to get hot after 10 minutes not running . , if its the early type with side dizy check cap & leads . I had 635 for 6 years electrics were very reliableso long as kept clean . Also check dizy cap for hairline cracks .Hard to get new parts for them now as BMWstopped making parts for them around 2009 .Check connections to thebox on the inner gaurdtoo . Sounds more like afuel problem .For infocheck out535wksp manual

richard198, Jun 13, 12:59am
OP is quoting no power at ignition coil.

pugmyre, Jun 13, 3:29am
Thanks guys.Will keep checking.Have bypassed all electrics to get going, also bypassed electrics to fuel pump, but 12 volts to fuel pump etc seems to be loading the system up.

bae13, Jun 13, 9:17am
should be an old motronic system, and have ignition coil driver in ecu, these commonly fail in most motronic eqipped cars, id pull out the ecu and resolder all the board first and see how it goes

elect70, Jun 14, 11:51pm
^^^ sayingpower ondistributor , doesnt say if got power to coil .That is the pre mototronic ignition systemtheecu is behind gloveboxrarely give troubleTry asking on the bimmersport forumsmight still be an 635 owner on there. Failing that getwkshop manual for 535 .