vr v8 wont run properly - cross posted

[rally_toy]

this is also in the VR VS forum
and a VR V8 race car that stopped on me last year when i went to start a race
good fuel flow, pressure, imobilser ok, injectors pulsing, all the usual obvious stuff came up as ok
i fitted a new distributor as some 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??

[Pub247]

you put it in diagnostics mode when doing timing?

[rally_toy]

yes
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'

[mr j-man]

yes
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'

i had the same prob once in the same type car.....they tried everything....then the last thing the tested was the coil and thats where the prob was...who wouldve thort!