Author Topic: Coil ignites with key on  (Read 2251 times)

Offline lsone_chevelle

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Coil ignites with key on
« on: December 10, 2019, 02:08:57 pm »
Hey guys,

Ive done a done of searching and have not been able to successfully find an answer.

The car is a obd2 MK3 VR6 12v golf with a Lugtronic PNP VEMS ecu.

The car runs, but I have an intake manifold that is split wide open that now needs to be repaired.

When I turn the key to the on position, but not cranking. The coil sparks, thus igniting any residual fuel. Intake valve was open when I turned the key and boom.

On the facebook vems user page a member replied saying "its an easy fix, google flyback diode. Which I did and I cannot find anyone that has fixed this issue. I posted in another group, a VR6 specific group and several members posted saying their cars do it as well and the just start the car every time at Wide open throttle to prevent blowing the intake up. That seems like an absolutely terrible band aid.

Can someone please help me get this sorted out?

Thank you for your time.

-Matthew

Offline MWfire

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Re: Coil ignites with key on
« Reply #1 on: December 10, 2019, 06:04:52 pm »
I think problem is in cable of crank sensors. It needs to be shillded and good grounded.

Offline GintsK

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Re: Coil ignites with key on
« Reply #2 on: December 14, 2019, 05:43:13 pm »
Something like this may happen when ignition outputs are 'inverted' in config (depends on wiring, internals. do not try to change to 'normal' with coil connected). Then  millisecond or so during boot outputs charge coil, then go to inverted state as per config and coil fires... Just my guess.