Distributor vs late coilpack OBD1 loom

[unclean 10]

Hi folks,

 

I'm in the process of swapping my '92 dizzy VR6 motor for a '94 coilpack motor, ECU and '95 engine loom. I've just extracted the original loom and was comparing the two, which I believed would be plug and play into the fusebox, and there's a couple of differences (it's never as easy as you think!).

 

I essentially have no idea what I'm doing with this kind of thing, so after some searching I found this page which seems to list the changes http://www.a2resource.com/electrical/management/motronicvr6aba.html, which look to relate to having the 94+ loom. However, this leaves me stumped with how I should connect them to the fusebox and whether they need to be spliced into the old connectors or be left disconnected :scratch:

 

Differences from dizzy loom to '95 coilpack loom:

 

- One of the '95 "G" plugs has a couple of extra wires going into it

- Different red connector on the yellow/red wire

- Extra single pin yellow connector with yellow/black wire

- Extra single pin black connector with violet/white wire

- Extra double pin yellow connector with black/red & brown/red wires

- No white connector with brown/white wire

- No red connector with black/red wire

 

I wonder if the yellow connector (black/red & brown/red wires) are an amalgamation of the earlier loom's white connector and red connector (black/red wire), which I believe are grounds?

 

Here are some pics!

 

"G" plug

 

 

Dizzy loom

 

 

'95 loom

 

 

Any help would be much appreciated.

 

Thanks, Phil.

[swiftkid 1]

The yellow connector with 2 wires is aux water pump, the black is k-line (diagnostic) and I can't remember the others off the top of my head. I'll try remember to look tomorrow. I'm guessing you'll have a 2x2 diagnostic plug so you'll have to swap over to the 16pin one

 

Just use the full loom and should just plug and play, shouldn't need to splice anything

Edited January 24, 2016 by swiftkid

[unclean 10]

Thanks for the reply. Interesting about the 2x2 and 16 pin OBD connector.

 

What I'm unsure about though, is that given the different connectors between the two looms, how I'd be able to just plug and play the new one?

[unclean 10]

I'm also not sure if it makes a difference, but my car has the early-style interior and dash cluster.

[swiftkid 1]

Apologies, I may have been talking crap. I always get mixed up between k-line and immobiliser. I think that purple one is your immobiliser so I'm presuming your new ecu ends in cp?

 

I'm just looking at what the other wires do. The yellow 2 wire plug should connect to the lighting loom and onto the rad fan controller

[unclean 10]

Haha, no worries.

 

Unfortunately I forgot to get a picture of the part number of the ECU before I fitted it, but I'll get it at the weekend.

 

After tracing the wire and consulting the Bentley manual, it looks like the violet/white wire is an MPG sender to T28/26 on the instrument cluster. Now, my car never had that, which the Bentley manual confirms, so not entirely sure if it's required. Probably safe to leave it disconnected for now though.

 

Interesting about the yellow two pin connector, I found some very similar wires which do what you say in the Bentley manual, but don't have the same colours. Perhaps that's not been updated on their part, or is different between LHD/RHD vehicles?

 

It also looks like the red/yellow wires with red connectors are the same between looms, just with a slightly different connector. The black/yellow wire runs through to a single connector at the other end of the loom, which wasn't present on my original loom at all, I'm having trouble finding out what it's for. Any idea Swiftkid?

[unclean 10]

Update, it looks the original brown/white wire has been replaced with the brown/red wire on the yellow two-pin connector in the new loom, which goes to the aux water pump in both instances (similar to what Swiftkid said). The black/red wire w/single red connector on the old loom has been combined into the yellow two-pin connector on the new loom, but is for the yellow coolant temperature plug in both instances.

 

Was a bit of a mission tracing these as the pinouts on the 42-pin engine loom connector have very different pinouts between the two era of looms!

 

To confirm if anyone comes here from google, the early loom is part number 536 971 072 AS and the late is 536 971 072 DJ.

 

Now I've just got to change the connectors for those two wires and also source a new MAF sensor, as the late one also uses a 4-pin, which I believe is hot-film instead of the original 5-pin hot-wire sensor.

 

Cheers, Phil.