Engine doesnt stop when ignition ‘off’

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100leelee
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Engine doesnt stop when ignition ‘off’

Post by 100leelee »

Hi
Two questions in one really, well a statement then a question..
1.9dg 1986 lpg conversion

So, after having the dash out, I tidied up the po mess of wiring, there was a push button starter etc that just wasn’t needed nor wired properly..
So changed petrol tank, electric pump and carb, as she ran exclusively on lpg, and I wanted the option to run on petrol..

She fired up on petrol, all good, ran rough but expected..
Turned key to off, engine still running..!!

I have a kill switch on the earth from the battery, turned this off, engine still runs!!

So the ignition switch is still live in the ‘off’ position, guess will need to double check the wiring to it.. although all I did was remove the utter bodge of a push starter..

Second is why does the engine run when I effectively disconnect the battery..?
I need to make sure there are no spurious earths before the kill switch.. don’t think there are though..

Any ideas!!??

Ta

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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

It's running on because (probably):

The alternator is generating electricity
The feed to the coil, fuel pump and carb cut off valves are still live from the alternator power when the key is in the off position.

You need to recheck your wiring, carefully, beginning with the ignition switch.

How do you kill it when running :shock:
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

937carrera wrote:It's running on because (probably):

The alternator is generating electricity
The feed to the coil, fuel pump and carb cut off valves are still live from the alternator power when the key is in the off position.

You need to recheck your wiring, carefully, beginning with the ignition switch.

How do you kill it when running :shock:


If it’s on petrol, turn off the fuel pump..
On lpg turn it onto petrol
Or stick it into 4th and attempt to drive off..

Not really sure how I’ve screwed it up, was very careful when removing the birds nest of wires behind the dash..
The PO really had wired things up badly..
The push starter was chock blocked off the ignition switch..
Nightmare
Thankfully she’s still in dry dock, so can take time sorting..
Would have still thought killing the earth would drop the LT side of the coil and stop her running

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itchyfeet
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Re: Engine doesnt stop when ignition ‘off’

Post by itchyfeet »

Seen this before.
there are two circuits to the engine
one is ignition live the other is thermoswitched.
mix them up and you get this
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
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100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

itchyfeet wrote:Seen this before.
there are two circuits to the engine
one is ignition live the other is thermoswitched.
mix them up and you get this

Can you mix them up ignition switch end?
And how is it sorted..
Electrics not my strong suit..!!!

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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

Wiring diagrams here

http://syncrosport.com/info/wiring/

The route to earth from the LT side of the coil is from terminal 1 on the coil (the green wire) that goes to the revcounter /BOD system. Easier to remove the coil connection at terminal 15 until the engine stops.

Looks like itchy has given you a good pointer :)

Oh, and your other thread....... I think you know the answer it's a PO bodge.
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

937carrera wrote:Wiring diagrams here

http://syncrosport.com/info/wiring/

The route to earth from the LT side of the coil is from terminal 1 on the coil (the green wire) that goes to the revcounter /BOD system. Easier to remove the coil connection at terminal 15 until the engine stops.

Looks like itchy has given you a good pointer :)

Oh, and your other thread....... I think you know the answer it's a PO bodge.

Cheers to both
Will take a read...

It’s amazing how the po thought he was better than the engineers at Vw..
Have stopped being surprised anymore, just sort them as I find them

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

100leelee wrote:
937carrera wrote:Wiring diagrams here

http://syncrosport.com/info/wiring/

The route to earth from the LT side of the coil is from terminal 1 on the coil (the green wire) that goes to the revcounter /BOD system. Easier to remove the coil connection at terminal 15 until the engine stops.

Looks like itchy has given you a good pointer :)

Oh, and your other thread....... I think you know the answer it's a PO bodge.

Cheers to both
Will take a read...

It’s amazing how the po thought he was better than the engineers at Vw..
Have stopped being surprised anymore, just sort them as I find them

Also noticed a thick red wire from Alternator back towards the dashboard
Always suspect additional wires

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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

That should be fine, see column 5 of the wiring diagram.

Take note of the colour and thickness of wires on the wiring diagram. 2.5 is chunky 6.0 is very chunky.

The thermoswitch itchy is referring to is I believe in current track 23, see where that cabling is connected to
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

937carrera wrote:That should be fine, see column 5 of the wiring diagram.

Take note of the colour and thickness of wires on the wiring diagram. 2.5 is chunky 6.0 is very chunky.

The thermoswitch itchy is referring to is I believe in current track 23, see where that cabling is connected to

Ok cheers
Only mentioned the additional wire as its not original....
Will take a look one evening this week, weather and work dependant!!

100leelee
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Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

Had a quick look tonight at this
Wiring to ignition switch looks as it should be, couple of wires spliced from it, but don’t think that sinister.. the green cable ( parking switch) just isn’t there.. for some reason..
Picture attached..

So still none the wiser really ..

Not sure where to look for this possible thermoswitch issue..
Can find it on the wiring diagram, all the wiring seems to be engine bay, and I haven’t touched any wiring in there since the engine stopped via the key..

As the wiring also has bits spliced into for the LPG switch I can see this being a nightmare....Image


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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

100leelee wrote:.
Have stopped being surprised anymore, just sort them as I find them

That means you have a good chance of sorting this.

I have looked at the picture and the wiring diagram. If you look carefully at the connector block the terminal numbers should be visible, it might help if you just write down what is there, and then compare against the diagram.

I agree, the green wire for the indicator driven parking light seems to be missing. Why, who knows, is it maybe dangling or connected elsewhere ?

The only thing from the picture is that the red/black wire / terminal 50 which is live from the battery should have a thinner friend along side it, the 1mm wire connecting to b4 on the fusebox and from there to the 7 pin connector in the black connector box in the engine compartment. Is that missing ?

Perhaps the PO has picked up a 12v feed to the coil from elsewhere in the engine compartments....... the thermoswitch which itchy mentioned ?

Get it sorted piece by piece and the problem will be solved, though the additional LPG wiring is something that others will need to help with
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

100leelee
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Posts: 519
Joined: 31 Dec 2016, 18:28
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Location: Dinnington, South Yorkshire

Re: Engine doesnt stop when ignition ‘off’

Post by 100leelee »

937carrera wrote:
100leelee wrote:.
Have stopped being surprised anymore, just sort them as I find them

That means you have a good chance of sorting this.

I have looked at the picture and the wiring diagram. If you look carefully at the connector block the terminal numbers should be visible, it might help if you just write down what is there, and then compare against the diagram.

I agree, the green wire for the indicator driven parking light seems to be missing. Why, who knows, is it maybe dangling or connected elsewhere ?

The only thing from the picture is that the red/black wire / terminal 50 which is live from the battery should have a thinner friend along side it, the 1mm wire connecting to b4 on the fusebox and from there to the 7 pin connector in the black connector box in the engine compartment. Is that missing ?

Perhaps the PO has picked up a 12v feed to the coil from elsewhere in the engine compartments....... the thermoswitch which itchy mentioned ?

Get it sorted piece by piece and the problem will be solved, though the additional LPG wiring is something that others will need to help with


Will double check tomorrow, am pretty sure the solid red (30) was live from the battery..
I have only worked on the wiring around the ignition switch, removing a push button starter that the po had installed. The van ran ok prior to this push button starter removal.. so whatever is incorrect I would hope is at the switch end..?
On a hopefully unrelated note, the wipers and heater blower work irrespective of ignition switch position..?
Electrics not my favourite :shock:

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937carrera
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Re: Engine doesnt stop when ignition ‘off’

Post by 937carrera »

Sorry terminal 50 is starter, brain fade :oops:

Here's a better reminder http://www.bosch-classic.com/media/en/b ... nungen.pdf

Wipers and blower should be off when ignition off - same issue as the reason why the van is running on
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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itchyfeet
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Re: Engine doesnt stop when ignition ‘off’

Post by itchyfeet »

100leelee wrote:
itchyfeet wrote:Seen this before.
there are two circuits to the engine
one is ignition live the other is thermoswitched.
mix them up and you get this

Can you mix them up ignition switch end?
And how is it sorted..
Electrics not my strong suit..!!!

if its only been changed ignition switch end then you may have the ignition 12V permanently connected to permanent 12V
check the voltage on the coil black wire to body with ignition switch off.
1988 DG WBX LPG Tin Top
1989 DJ digijet WBX Holdsworth Villa 3 Pop Top
itchylinks

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