using petrol wiring loom for diesel conversion

for questions and answers about alternative power transplants on the T25, GTi, Porsche,Subaru etc, this is the place. You must register to post but anyone can read.

Moderators: User administrators, Moderators

Post Reply
h2865
Registered user
Posts: 17
Joined: 13 Oct 2011, 12:29
80-90 Mem No: 0
Location: Chester

using petrol wiring loom for diesel conversion

Post by h2865 »

Now then ladies and gents,

after a couple of weeks humping and grunting ive managed to do the conversion from a 1.9DG water cooled engine with an Auto box to a 1.9TD AAZ engine with manual 5 speed box. the engine runs and sounds great however i have a number of issues to try and sort and after many head scratching hours I've run out of ideas.

can anyone out there assist by telling me which wire goes where for ALL the sensors. At the moment to run and stop the engine i have to remove the wire from the fuel cut off sensor which i wire to the + side of the battery. any help will be greatly appreciated

Please bear in mind I'm using my original petrol loom as the diesel one was trashed by the person i bought the engine from. Or is there anyone out there locally who will allow a visit and a quick look if they've done the job already.

User avatar
syncroandy
Trader
Posts: 1857
Joined: 18 Oct 2005, 18:15
80-90 Mem No: 851
Location: North Lancs. UK
Contact:

Re: using petrol wiring loom for diesel conversion

Post by syncroandy »

You might be better off getting a complete diesel engine bay harness including the GP relay from a breaker, and using that as a basis for your job. Get a 'late' one which has sender connectors that'll better match the ones on your AAZ.
Syncrosport
Volkswagen Transporter, reloaded.

252 GC5 EJ25 AAN L90D
246 097 AFN AVL+ L90D
Syncronaut #004

h2865
Registered user
Posts: 17
Joined: 13 Oct 2011, 12:29
80-90 Mem No: 0
Location: Chester

Re: using petrol wiring loom for diesel conversion

Post by h2865 »

thanks friend certainly something to think about but not being an auto electrician if i went down that route (engine harness) what happens to the existing wiring harness from the petrol side do i simply blank them off

sassy
Registered user
Posts: 102
Joined: 07 May 2010, 14:05
80-90 Mem No: 8491
Location: Southampton

Re: using petrol wiring loom for diesel conversion

Post by sassy »

We did exactly what you've done engine wise.
Converted a petrol van to 1y diesel.

I used the existing petrol loom and with Haynes manual decoded what colour wires went to the sensors on the original engine. Then it was a case of soldering wire onto these so they can reach the sensors on the 1y.
I didn't use the multiplug as it was overkill for the few wires that are actually needed!
You should have one on the oil cooler and another on the side of the head that faces the front of the van. They are oil pressure I recall.
Water temp is a multiconnector off the head I believe.

The fuel pump (fuel cut off solenoid) just needed a switched live from memory, that was in the existing petrol loom found again on the petrol wiring diagram.
It was a couple of years ago so a bit hazy but I did it without needing the diesel loom.

If you were at all close to Southampton I'd offer to come and have a look!

h2865
Registered user
Posts: 17
Joined: 13 Oct 2011, 12:29
80-90 Mem No: 0
Location: Chester

Re: using petrol wiring loom for diesel conversion

Post by h2865 »

Sassy,

Thanks for your reply and apologises for not responding sooner but I had other commitments to fulfil (decorating and the like). Distance is clearly an issue. However are you able to further assist by checking your wiring and PM me with a basic diagram anything would be a bonus

Regards h2865

Post Reply