MembersPage/PerBoddum/SierraCosworth (2014-11-17 22:12:39)

Sierra Cosworth 1986


Original Cosworth trigger system

8 crank trigger + 2 distributor triggers 90 degree apart (180 crank degree).

Problem 1:

Have to power down ECU 3-4 times before engine will start (ignition pulses does not appear in triggerlog).

Problem 2:

Seems that ECU must recieve 8 distributor pulses before ignition is enabled and the engine will fire up. So have to crank at least 6 sec before engine fires

VR scope signal primary+secondary trigger

vr%20scope.png

When cranking it seems that the ECU must recieve 8 secondary triggers before ignition is enabled. This means that it must crank more that 6 seconds, before starting.

3 out of 4 times it will NOT start (no ignition pulses), even after 15 seconds of cranking and really good triggerlog with no errors at all.

When not starting the triggerlog looks exatly as the triggerlog below when cranking. All triggers are evently spaced and equal in length and time from 0 sec. to 15 sec into the triggerlog.

During the 0 to 15sec cranking there are no ignition pulses.

I have to power the ECU down and restart several times before ignition pulses appear in the triggerlog and the engine fires up right away.

http://www.vems.hu/files/perboddum/Cosworth/test20%20inverted%20vr.triggerlog

Log starting and running

http://www.vems.hu/files/perboddum/Cosworth/test20%20inverted%20vr.vemslog