Firstly I'm on MSD wasted spark.

Has anyone ever had an ignition amp break down due the heat in the engine bay? I've problem where if the car is sitting idling for a long time (15+ minutes) it'll go onto two cylinders. If you open the bonnet/drive the car the fault clears, so it's down to the hot air trapped in the engine bay.

The coil pack is only a few hundred miles old. One of the ignition amps is a few K miles old, but the other is the original that was on the car and I've not replaced it since I've owned the car (2007).

The only things i can think of that would cause this fault are one of the ignition amps plying up when hot, or once side of the coil pack going faulty.

Any other ideas?

 

have you got on the back of the amps white grease?

 

Yep they were done with heatsink compound when I fitted the wasted spark kit. You think it could just need redone?

 

..why not try it ,,you never know with cossies...just to add i have also ws kit but had starting hot problems with that ford coil..at least this is the part i replaced ... so i got from usa msd one..after that i dont have any starting issues...
also try a put a bit of dielectric grease on the inner part of the plug leads but be sure that the grease dont touch the metal contact....you can see on spark plugs discolored part on the ceramic..probably that one will have issues..it might help ..cheers

 

Thanks mate

 

I had wasted spark on my escort at one point, had a lot of trouble going onto 2 cylinders, the wasted spark driver was getting hot in the ecu, removing the lid allowed it to run for longer.

 

That's something to check as well. However the ECU in mine is behind the glovebox so I doubt it's getting that warm? Plus it's only when the car is stationary, which points to hot air in the engine bay being the problem?

 

What is the alloy heat sinc you have it on.

Mark

 

One of the MSD twin amp brackets.

 

Can you identify which 2 cylinders it drops?

The wasted spark coil is basically 2 coils, one side sparking 1 and 4, the other sparking 2 and 3, if you can find out if the 2 cylinders it drops matches this then there is a good chance its one side of the coil dropping out and definitely spark related, if its not maybe it fouls plugs etc?

If the issue is one side of the coil dropping out, swap the amp plugs over, see if the problem follows,(it should change to the opposite coil) this will tell you if its amp related. if it stays on the same side of the coil, it could be coil, or a driver/loom issue.

 

It's really really hard to get the fault to occur. It's only done it twice in a year and a half...

Suppose I could heat gun the suspected components see if that causes the faults, then try your test?