Holden V8 5.0 VP EFI Won't Go No Spark ????

[suzolla]

Hi,
Was running fine.
Went to start it in the morning, fired up then stopped, as cold. started again and fired up then stopped, tried again, no go, no spark.
Looking for some advice where to look first.
With the ign on there is power to both sides of the coil ?
When I crank it both sides of the coil stay on, test light stays on.
With test light across coil it stays on, think it is meant to flash ?

What do you think

Cheers
Tim

[Big]

I had a very similar thing happen to me but turned out to be the tps sensor.. I would check it if you are running one otherwise check fuses to rule out that side of things..goodluck

[MihiT]

I don't know about your application in particular, (module, points, distributor) but yes, the coil is supposed to collapse it's field for each cylinder, giving you the high voltage spark. (And the flashing light) This should be open circuit rather than to-ground, I don't quite get how you're measuring it?
When "on" and not running your coil should be energised (12v from + terminal to chassis)

You will need an LED probe to catch the coil collapse signal as the rise time is too fast for old incadescent testers. Unless you turn the engine over by hand.

The first and easiest diagnostic is to crank the engine in a dark garage and look for loose sparks, either off your HT leads or the coil clamp.

How did you get to the no-spark diagnosis?

[Crash bandicoot]

Not uncommon. If the coil is charged then its not getting triggered to discharge.


Efi relay is common power for coil and ignition module...give the black plug on the module a wiggle or spray some wd40 into the plugs as well.

The trigger wire is brown/red from the module to the coil.

[skidmark]

Have had to change ign modules a few times on them..I believe they get dry solder join to inside the module by memory

[suzolla]

Thank for the comments,
I am using an LED probe, with the ign on both sides of the coil are +ve, read on the net that with test light accross the the coil it should flash when cranking, it did flash one time when I was testing but now nothing.
No spark from coil output in the dark.
Looks like the ign module can fail from cracked solder joints, will pull apart and have a look.

Cheers
Tim

[derk]

just commodores forum in Oz is the place you want to be looking if you haven't already been there mate

[suzolla]

Cheers, yes had a bit a look on just just commodores and aussieV8.

Anyone in Hamilton area that would have an ign module I could borrow to see if it works.

Cheers
Tim