vr ss race car no start

[rally_toy]

i have a v8 ss (hsv enhanced) manual
its a sprint/race car all stripped out
no ABS, AC, heater etc
recently did a lot of work on it including striping out the wiring loom
has an aftermarket fuel tank and bosch 044 pump etc
all ran ok, did 10 or 20 runs at the track so 60 or 70 km
went to start a run, pulled away from line, did about 5 metres, hesitated, ran for a few more seconds then stopped
not started since
pump pressure is fine and so is flow
plenty of voltage at pump and coil
strong even spark at plugs
immobiliser is turning off as it does turn over and you can here the relay in the BCM click when you turn it off
most the things that spring to mind like plugs or leads or pressure reg i wouldnt think would fail in an instant or stop it from starting just give you a rough run
cam is turning (checked thru oil filler in cam cover)
only error code is 31 and i beleive that is to do with security system which isnt suprising as all the central locking, door witches etc have gone)
any ideas?
am i right to assume injection gets its crank position signal from hall effect sensor in distributor (seeing as it has spark that must be ok)
put the digital multimeter on the injector plug to measure duty cycle but got no signal (either means its getting no pulse or its just a signal my MM cant read)
another question........ the ring on the steering column that surrounds the key barrel i assume thats just to charge the key battery?

[rally_toy]

didnt get any help with the last post so thought i would bump it up by updating
did read somewhere that even if u have spark didnt mean the hall effect sensor in the distributor was ok as it might be producing a signal ok for the ignition but not for the efi
so replaced the distributor
starts but intermittently
idle is rough and is very hard to get timing right without it stalling
and if u bridge pin 5 and 6 on the diagnostic port (as u are supposed to when setting the base timing) it wont start at all or if u bridge it when it does run then it wall stall

[Brett_jjj]

The ring around the ignition switch is not there to charge the ignition keys battery,these keys dont recharge,they have a normal non rechargeable button type battery.The metal ring is actually for the key to send a security signal to the BCM, which then sends a signal to the ECU, which then allows the injectors to operate, which allows the car to start.(immobilser system).The car shouldnt stall when the diagnostic plug terminals 5 and 6 are bridged.Id check the wiring at the ECU wiring connectors for a bad connection.Also code 31 will set when the ECU doesnt recieve a signal from the BCM to allow the injectors to run.This error code, when active, will cause a one second delay in the operation of the starter motor when the ignition switch is turned to the start position.

[rally_toy]

ok will put back that ring for the ignition key
i have raced the car since i took it out but weirder things have happened

[rally_toy]

ok i put the ring/wiper thingo for the key but still no go
it did kick over once but that was it
btw i get no delay in the starter operation so at a guess doesnt sound like its the immobilizer
will try leaving the ignition on for an hr and seeing if it starts then but i did try that before i changed the hall sensor and it didnt make a difference

[rally_toy]

after some time i have had a chance to look at this again
i fitted a new distributor as some other checks made the hall sensor the most likely culprit
after some issues with timing it up the car ran
i set the base timing to 10 BTDC
when i turn the car off it wont retstart unless i wind the ign back to about 30 BTDC
no fault codes (well just ones about pollution and AC but they both removed so understandable)
fitted new ignition module
no change
idle is good but it missfires when you try and rev the engine
clue
tacho needle does swing back to '0' when u back off the throttle
question
does the MAP sensor affect timing?
does the main ECU affect timing or is it all controlled by the ign module?
i cant see a bad coil breaking down so badly.... any thoughts??

[Commydoor]

if it was carby without electronics i'd of said it had a bad vacuum leak at the manifold...

[BottleFedVS]

if you have replaced the distributor (im assuming the new hall effect trigger was in it), it may be the ignition module on the passenger strut tower,
as that is the interface for the hall effect trigger.
A bad coil can also do that.
i hope that helps.

[rally_toy]

i have replaced the ignition module
i will try the coil but if it is that then i will be first one i have ever had to replace

[Smitty]

............
i will try the coil but if it is that then i will be first one i have ever had to replace

if its the original it should be dead by now

i havent heard of a std EFI coil (VN-VS) lasting more than about 10 years
back when the first one died on my VR ...it got replaced under warranty thats how quick they do!

I have helped mates replace them since..they just die (beware they dont take the ignition module with them)

[VrWagz1]

Are you setting the timing to 10 degrees in diagnostic mode??

You would possibly get better answers if you would have posted in the V8 304 section. Its all the 1 forum, but people like myself wouldnt have a clue what the other 80% of the forum is doing. I stick to vr/s section and 304 section.

[rally_toy]

yes its diagnostic mode
the coil isnt original but i will try it anyway
is about all thats left in the ignition system lol

[rally_toy]

and all good now
was the coil
last thing i would have expected
in 20 yrs of playing with cars and my dad 45 yrs as a mechanic....... never had a coil 'play up'........ maybe die completely but never cause missfires and timing issues
only thought is that as it was going open circuit or giving a high resistance and that was causing the ign module to give a bad 'spark timing'