304 ignition problems

Wiring diagrams and questions
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djbrooksy
Posts: 159
Joined: Tue May 05, 2009 6:41 pm
Location: Launceston TAS

304 ignition problems

Post by djbrooksy »

Hi gents
I have a mates vl parked in my driveway with a few problems
The biggest of all being no spark

When he brought the car a few months back it would randomly just die, so he brought a refurbished ignition module and all has been well till last Friday Then it just up and dies.

After pulling the coil out he found it cracked so put new one in
And still no spark. So the he puts a new hall sensor in the dizzy still no spark.
At this point he tows it to my place and tells me to fix
So after a few checks I found power to the coil is only 8v
Same at the module ( scratches head ) and coil get dam hot

Now if I unplug the coil I get full power at the module
Or If I unplug the module I get full power to the coil ( more head scratching )

Looking a the wiring I couldn't any reason for it even with the dodged up mess it is

So I pull dizzy, coil and module out and bench wire it together and well same results. Spin dizzy no spark coil gets hot and only 8v at coil and module.


So after all that dribble what's the thoughts of the brain trust
Has the module gone tits up again?
Is there any tests that I can do confirm my thoughts
Dylan
Posts: 3355
Joined: Mon Aug 02, 2010 6:35 pm
cars: VR Commodore V8

Re: 304 ignition problems

Post by Dylan »

Ive dealt with a few reco modules grom places like Repco etc. They are terrible and play up all the time.
Would be great to find a trusted original one to try.
vlt304
Posts: 226
Joined: Wed Feb 27, 2013 8:46 pm
cars: eh premier sedan v8 vl commodore

Re: 304 ignition problems

Post by vlt304 »

sounds like the module is shorting the coil neg to ground the big switching transistor is what fails most of the time in the module easy to fix.
djbrooksy
Posts: 159
Joined: Tue May 05, 2009 6:41 pm
Location: Launceston TAS

Re: 304 ignition problems

Post by djbrooksy »

That's what I was thinking
But having never had to fault find on the v8 ignition I wasn't sure if I was missing somthing
djbrooksy
Posts: 159
Joined: Tue May 05, 2009 6:41 pm
Location: Launceston TAS

Re: 304 ignition problems

Post by djbrooksy »

Got the module replaced under warranty
And it's alive again.

All I need to find now is how to get it in diagnostic mode to set the timing, I thought all I had to do was put pin A9 to ground
But when I do so I am still seeing advance when you give it a rev
Dylan
Posts: 3355
Joined: Mon Aug 02, 2010 6:35 pm
cars: VR Commodore V8

Re: 304 ignition problems

Post by Dylan »

It is A9 from memory on an 808. What model ecu is it fitted with?
Is the engine light flashing? It's only fixed advance under 2000rpm.
djbrooksy
Posts: 159
Joined: Tue May 05, 2009 6:41 pm
Location: Launceston TAS

Re: 304 ignition problems

Post by djbrooksy »

Yeah its a 808
And if it's only under 2g that would be why
Cheers
djbrooksy
Posts: 159
Joined: Tue May 05, 2009 6:41 pm
Location: Launceston TAS

Re: 304 ignition problems

Post by djbrooksy »

The heap of puss is still being a batch
The thing will only start when the module is warm

I never had a problem with it as it had sat in sun all day
He picks car up takes it home next morning won't start, no spark
Later that day without touching a thing it starts.

Morning after that same thing, puts it on a trailer tows It to a mechanic, mechanic calls saying it's fine can't find a problem

This morning same thing no spark, as bit of a joke told him to put a heat gun on the module for a minute or two
And I shit you not it started.

Seriously can these refurbished units be this dam crap
Dylan
Posts: 3355
Joined: Mon Aug 02, 2010 6:35 pm
cars: VR Commodore V8

Re: 304 ignition problems

Post by Dylan »

Yes theu can. Saying this from experience.
Charlescrown
Posts: 1831
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Re: 304 ignition problems

Post by Charlescrown »

After 3 modules on the car I would start looking elsewhere. What about the wiring, electrical terminals etc. Might pay to get a diagnostic block diagram and start testing.
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