Your half way there! Connect your O-scope up to the input side (wiring side of plug) of the ignition module/multiple power transistor assy mounted on the end of the cylinder head opposite the fan belt end. A gray plastic package 2 mounting screws.
7 wires one side a to g(6 inputs from engine ecu and 1 ground) and 6 the other 1 to 6 (all grounding or pulling low each ignition coill)
You ought to be getting similar pulses on each input and similar on the outputs, if in's are ok and out's not then I'd suspect the module or it's connectors. It's a fault I've seen a few times exactly as you describe with some firing some not. Sometimes it will get worse when heating for 10 minutes with a hot air gun
'not too hot though'
If all the in's are not ok I'd be checking if the connectors are clean or back at the ecu connections, I havn't had a ecu cause the fault you describe, although you may be first !
When replacing the moduleClean off the module mounting surface with meths or similar then use a thermal conductivity paste sparingly and do not overtorque otherwise you'll distort the replacecment module and it'll have a hard time transfering the heat.
Do your tests with a fully charged battery so your results are consistant
Good luck !
Thursday, November 1st, 2007 AT 3:14 AM