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hi Guys,

As the title says, the ignition system in my Senator has given up the ghost.

Engine died suddenly no warning or anything. I was just accelerating out of an intersection with moderate throttle, no funny sounds or anything, just dead. Engine turns over fine.

Thought it was a fuel system issue initially as it seemed the pump had died (couldn't hear it priming with the ignition switched on) and it lacked fuel pressure. Changed the filter today and put a pressure gauge in the line before the fuel rail and it primes the system fine with ~43psi of fuel.

Tested ignition with a spare spark plug earthed against the intake manifold but no sparky sparky when we turned it over (have taken out the fuel pump relay to prevent fuelling up the cylinders any more than we already have as we could smell fuel at he back of the car).

I have a spare coil so I will swap it out tomorrow however I'm thinking it's either the distributor or ignition module that has failed by the way it died suddenly.

What I'm wondering is if anybody knows any quick ways to test either on the car.

I can possibly borrow another module but might have to wait a week or so before I can get it.

Cheers

Get a test light and see if you get pulses across the coil terminals. Mine did the same thing. Was a cracked coil.

Ive tested the hall effect sensor in the dissy before with a multimeter checking for voltage at the plug on the dissy.
Either back probe at the dissy or at the module. The correct way in the Hoden manual is to measure the current draw while cranking.
But ive done it a few times now with multimeter checking voltage while cranking.

Cant remember the figures but the crook ones are a few volts down compared to new ones.
But unlucky for you at the moment both the hall sensors and the modules are prone to sudden failure.

Yeh could be either of these things. On mine I had to replace the coil but it's not behind the engine any more as I think the heat down there doesn't help. Funny enough I have never had to replace the module( touch wood)but I do replace leads plugs,cap and rotor twice as offen as I should so that might help(maybe).

Cheers guys,

I'll replace the coil today as I have a spare. I suspect it still has the original coil and it's still the the factory location to boot.

Looking through a factory manual it shows that the distributor output should be about 11 volts for the signal so I'll see if I'm getting that at the plug on the module. Bloody dizzy is a PITA to get to with it in situ with the stock bananas manifold

the easy way we were able to test my brothers car for the same thing was I had a vn dizzy out of the motor and I just took it to his place with some hookup wire, plugged them into the right pins on the VT plug and turned the dizzy and we got spark, so that told me it was something in his dizzy.

but if you have a spare coil that's probably an easy place to start ... weather you have a spare dizzy is the question I guess

Id have to double check a diagram but i think the dissy wires go back to the module?
Might be able to test them there bit easier access anyway.

Chances are it is the module or the hall effect sensor

Used to shit me to tears in my old burnout car which lead to it being sold

A guy on ebay called nuclearmodules sells high quality replacement modules

Right, some quick testing this arvo.

The dizzy does indeed connect back to the module via a 4 pin plug. Back probed the signal wire from the dizzy (at the module plug), turned it over and got stuff all voltage.

I then unplugged the dizzy and checked the voltage output from the module to the dizzy and I'm only getting about 4.7 volts.

The Holden Factory service manual for VT/VX says to test the dizzy using a 12 volt source, to me this would indicate the problem is with the ignition module as it would seem it's not putting out enough voltage to the distributor for the sensor to work correctly?

Try a separate earth say bolt on strut tower?