MoTeC Global Forum

I have a M48 running a wasted spark system on my sierra cosworth. it uses a 36-1 trigger on the crank.
Was driving along a few weeks ago when all of a sudden it started misfiring badly. I noticed EGT rising quickly as the timing was being retarded.
Checked timing using a timing light and cylinders 2+3 plugs(which are paired on one half of the wasted spark ignition system) are holding their timing values 100%
The plugs on cylinders 1+4 are firing wildly, about 60-70 degrees variation. I have replaced the coilpack and ignition modules but the problem still remains on cylinders 1+4?

Could this be an ECU problem????

Thanks in advance for any help
John

What type of ignition module and coils are you using?

2x Bosch Module 1227 022 008
Standard ford twin coilpack

I have found that I can cure the problem by unplugging and immediately reconnecting the ignition module connector. It then runs fine for 2-3 minutes before the problem returns. Unplugging it again will solve the problem for another 2-3 minutes
It is definetly not the module connector as I have checked this several times,

Have you tried pushing the receptacles out of the module mating connector?
I have seen the retaining tab break off, when you disconnect and look into the connector all looks fine but when you connect it the pins on the module push it back into the connector leaving it touching but not properly connected.

Yep tried that. I have ran new wires to all the ignition parts so im fairly sure its not wiring problems

Assuming that you have checked all of your conections to youe module and coil, you may have a connection problem to the ECU. You need to remove the pin (pin 33) from the ECU connector and check that the flap in the pin is pushed up as shown in the atached drawing. If it isn't the connection will be intermittent which could cause the erratic condition you are describing.