Glow plug wiring woes

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Drawl21
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Glow plug wiring woes

Post by Drawl21 »

Good afternoon all
I’ve recently acquired a 1986 16 turbo diesel (JX)camper,the previous owner has wired the glow plugs up to a push button on the dash,the van now isn’t starting,turns over but doesn’t fire,possibly the glow plugs but it could also be the PO’s wiring,it’s terrible,has anybody rewired the glow plug circuit so it works as originally on the key?,If anybody has any hints,tips,info or diagrams that would be great and really appreciated,thanks Dave
1987 t25 crew cab 1.6 n/a diesel

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Mocki
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Re: Glow plug wiring woes

Post by Mocki »

Have a read of this 
viewtopic.php?f=12&t=141982
gives the wiring colours and pins outs , but no actual diagram 
 
Steve
tel / txt 07947137911
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just one shade of very fast grey
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1989 2.1LpgWBX HiTop Leisuredrive Camper

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Mocki
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Posts: 15490
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Location: Mansfield tel/txt 07947137911
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Re: Glow plug wiring woes

Post by Mocki »

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Steve
tel / txt 07947137911
Image
just one shade of very fast grey
________________

1989 2.1LpgWBX HiTop Leisuredrive Camper

Drawl21
Posts: 80
Joined: 27 Apr 2015, 10:11
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Location: manchester

Re: Glow plug wiring woes

Post by Drawl21 »

Thanks Steve,the PO wired the glow plugs through a large relay in the engine compartment,the original black box and relay is still there by been by-passed,the yellow light on the dash still comes on and goes off but has no relation to the plugs anymore,I’d rather try and put it back to work on the key than figure out his wiring,will have a read now,thanks again
1987 t25 crew cab 1.6 n/a diesel

davidoft1
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Re: Glow plug wiring woes

Post by davidoft1 »

how long are you holding in the glow plug button, can you hear the relay operate? 

i think i have a spare heater plug relay loom etc 

Drawl21
Posts: 80
Joined: 27 Apr 2015, 10:11
80-90 Mem No: 14412
Location: manchester

Re: Glow plug wiring woes

Post by Drawl21 »

Hi,the previous owner has completely bypassed the original relay and wiring and put a push button on the dash which runs through a really big aftermarket relay in the engine bay,I’d rather do away with all that and go back to stock,I’ve bought a new sender and relay,just waiting on the glow plugs being delivered,how easy/difficult would it be to fit a different glow plug loom?thanks for your reply
1987 t25 crew cab 1.6 n/a diesel

davidoft1
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Location: hayling island

Re: Glow plug wiring woes

Post by davidoft1 »

Drawl21 wrote: 07 Jan 2021, 18:20 Hi,the previous owner has completely bypassed the original relay and wiring and put a push button on the dash which runs through a really big aftermarket relay in the engine bay,I’d rather do away with all that and go back to stock,I’ve bought a new sender and relay,just waiting on the glow plugs being delivered,how easy/difficult would it be to fit a different glow plug loom?thanks for your reply

you said it doesnt run any more ? how long are you holding in the glow plug button?  

why would you choose to rewire it rather than just returning to stock? the heater plug relays were for a time near impossible to buy so presumably thats why the push button was fitted, its pretty common on old diesels 

Drawl21
Posts: 80
Joined: 27 Apr 2015, 10:11
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Location: manchester

Re: Glow plug wiring woes

Post by Drawl21 »

Yeah it turns over but won’t fire,I am trying to return it to stock and have it work off the key again,I’ve pushed the button in for up to a minute and it still won’t fire
1987 t25 crew cab 1.6 n/a diesel

davidoft1
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Joined: 27 May 2009, 18:56
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Location: hayling island

Re: Glow plug wiring woes

Post by davidoft1 »

Drawl21 wrote: 07 Jan 2021, 18:51 Yeah it turns over but won’t fire,I am trying to return it to stock and have it work off the key again,I’ve pushed the button in for up to a minute and it still won’t fire

have you ever had it running ? 

do you have the original loom still in place?
why are you changing the heater plugs?
can you hear the heater plug relay work when you press the button?
does the heater plug light on the dash operate?
 

Drawl21
Posts: 80
Joined: 27 Apr 2015, 10:11
80-90 Mem No: 14412
Location: manchester

Re: Glow plug wiring woes

Post by Drawl21 »

Yeah I think the original loom is still there but it’s been hacked about,the original relay in the black box isn’t being used anymore but it’s all still there,the previous owner has fitted an aftermarket relay in the engine bay,the 4mm power cable from the battery now runs to the new relay,I’ve not heard this relay click,I want to use the original relay in the black box not the new one,yeah the yellow light comes on and stays on for around 20 seconds,I was thinking if I could re- route the thick live back to the black box it might power the stock relay and then re-wire from the relay to the sender,glow plugs etc,I’ve ordered glow plugs just in case
1987 t25 crew cab 1.6 n/a diesel

davidoft1
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Joined: 27 May 2009, 18:56
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Location: hayling island

Re: Glow plug wiring woes

Post by davidoft1 »

I suspect that it’s still wired in bar one or 2 wires, does the dash light come on with the ignition or the button,got a picture of what’s been done ?

Drawl21
Posts: 80
Joined: 27 Apr 2015, 10:11
80-90 Mem No: 14412
Location: manchester

Re: Glow plug wiring woes

Post by Drawl21 »

Yeah that’s sort of what I was thinking,the yellow light comes on with the ignition and stays on like you’d expect,I’ll have a look at it over the weekend(if it dries up a bit),I could put some pics up tomorrow,if it still looks like I need the glow plug loom,I’ll contact you to see if you have it and how much it is,thanks for all your replies
1987 t25 crew cab 1.6 n/a diesel

hubcap61
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Re: Glow plug wiring woes

Post by hubcap61 »

Check ou this link
https://vwt25.blog/files/
Has the manual for diesel injection and glow plug systems.
free dowmload.
 
1984 Caravelle 1.9 DG 34 DAT
2002 Audi TT 225 BAM.

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