3.2 digi (abf) into 90spec mk2 wiring help

[Simeon]

Currently trying to sort the loom for an abf swap but wiring is not a strong point so please bear with me as I ask the same old questions - I have had a search by the way, but no-one has any pics or anything and I can't work out wiring diagrams at all. Big thanks to Rubjonny though for the fusebox faq, been very helpful.

Right, mk2 is a 1991 16v; bought a complete mk3 16v on P plate (1996) to do the swap. As it was a late mk3 the lighting loom and engine loom were together so have been removing all the lighting loom. I want to use the mk2 coil set up.

So far have removed from the mk2 engine loom to fit to abf loom;

Outside air temp
Wipers
Reversing light

Just the coil set up to go ... first problem, which wires do I need ..?.. I get confused because there seems to be a lot wired together although I understand it needs to be wired same as a mk2 digi (which is no help as this is obviously wired as a mk2 k-jet  ) On photo;

1 - TCI plug; 4 wires, earth, brown/blue to ecu plug, green to coil plug and black to side of coil (No. 6)
2 - Ecu, one brown/blue from tci above and black/white to side of coil (No. 6)
3 - Idle switch on throttle body; Wired into G1 pin 4 along with black wire to top of coil (No. 5)
4 - Coil plug; Green to TCI, two red/black wires -> one to G1 pin 12 and the other to a 6pin plug .. to clocks? rev counter?



This is the 6pin plug with the red/black wire that doesn't go to fusebox;



Finally, on the mk3 loom I have three wires that come from the ecu and go to two plugs which I think are something to do with the carbon canister. These are the two plugs;



One is brown/blue and white/yellow
The other is green/yellow and black/white - the black/white goes into G2 pin 4 along with two other wires

Also have a random purple/white wire that goes from the ecu plug to a 3pin plug, of which the other two wires are black/white to A1 pin 2 and black/green A2 pin 4 .. indicators? Why a wire to ecu?

All help gratefully received  preferably in 'stupid speak'   

Cheers

[richard s]

do a search for abf wiring and look through my thread its 5 pages and all the answers you need are on there. its a while since i did it but it was something like an earth and one of the cables from the mk3 coil loom spliced into the tci loom

[Simeon]

Cheers mate, I have read your thread, I just wanted some clarification really especially on the wires coming from the mk3 ecu

Also, what is the 'tci loom'? The wires coming from the tci plug go all over the place

[rubjonny]

I keep the mk2 outside temp wires as they're the right length to ereach stock location, mk3 too short as its on driver side of car. should be alright to find somewhere to put mk3 sensor on driver side tho, its your call.  you deffo need the mk2 wiper wires though, the mk3 ones are way too short to reach!

1. keep all the wires to the tci plug, connect this to the car as it was before. chop old ecu wire to tci pin 6 and splice this to the red/green wire on the MK3 coil. brown wire to mk3 coil no longer needed chop out and bin. black wire connect to +ve side of coil. but what i do is keep the MK2 golf coil wires, and chop out the mk3 coil wires.

2. chop the wire to tci and keep the black wire to the TCI-H unit as above, remove the old ecu black/white wire from the coil plug.

3. not required

4. keep all the wires as std, just chop out the 2nd red/black wire to the spade as this is for the old tci-h unit. black wire is ign live feed to coil, red/black is rev counter feed for dash. mk3 rev counter comes from ecu, but wont work mk2 dash. pop mk3 rev counter wire out and pop mk2 one back in

6 pin plug is mk2 isv control unit, you dont need this

last 2 plugs are carbon canister valve, and inlet air temp. dont need the carbon canister valve, bin. its the one with green/yellow and black/white wires. follow the wiring for it back and chop out.

wire to ecu is for the MK3 MFA MPG gauge, it gets signal from ecu rather than from vacuum pipe

[Simeon]

Thank you very much for that info John, very helpful. Got a couple of follow up questions;

In point 1 in your reply you say you keep the mk2 wires and chop out the mk3 ones. I presume by this you mean the remaining black wire in the mk3 coil plug (brown one chopped out and red/green spliced to pin 6 of tci plug)? It goes to G1 pin 4 the same as the mk2 one .. but there is also a black wire spliced in with it that goes to a 3pin plug on the engine .. annoyingly unlabelled on my loom. Should I just chop off the mk3 coil plug and splice on the single pin connector for the mk2 coil?

In point 4 in your reply; You say chop out the spare red/black wire .. this is the one that goes to the 6pin plug that you say is for isv control unit right? The other red/black wire that goes to G1 pin 12 is for the rev counter right?

The purple/white wire that you say is for the mk3 mfa mpg can be chopped out right? Presume you can hook up the vacuum pipe from the mk2 to work that function?

I also have two other plugs that I can't identify; One is single pin with a plain blue wire (labelled 'to alternator' on my loom) which goes to plug F pin 4. The other is a two pin plug (labelled 'gearbox') which has a black/red to F pin 5 and a black/blue to F pin 8. I thought this was mk3 reversing plugs and was just going to swap in the mk2 wires, but in this case where I would be putting the black/blue to F pin 7 I have a brown wire on the mk3 plug and where I would be putting the black/red wire to F pin 6 I have a red wire on mk3 plug...? confused

What is the block that is located under the header tank on mk3? I have a brown/black wire from the plug off this to a temp sensor that is screwed into the inlet manifold - presume this is for fan run on? What do I do with this wire as would like to maintain this function.

Finally, can I just remove the brown and black wires to two pin plug that goes to a blank in the inlet pipe .. believe this is something for cars with a/c (which mine didn't have).

All advice gratefully received.

[rubjonny]

with the coil wires you can either use the mk2 wires, or the mk3 wires. its totally your call
you'll find that the mk3 plugs and the mk2 plugs both have the same pins in use, so if you fit the mk2 coil wire you'll need to splice the mk3 wire to it. this is because the wire on the mk3 plug also does a few different bits on the mk3 loom, isv, ecu, etc. mk2 just does the coil.  I use the MK2 wire because its chunkier, though the mk3 wire will probably be ok.

if you use the MK2 coil wire, follow the mk3 black wire back till you find where it comes from, and chop it out. on the mk3 you'll see there is a joiny piece where several black wires all come together, you'll know what i mean when you see it. if you use the mk3 wire, simply crimp a spade on there and pop it onto the mk2 coil

on the mk2 coil plug, you'll see there is a short length of red/black wire with a spade on poking out the back, this you can chop off as its only needed for the 16v isv controller. you could just leave it on but unplugged if you like!  the main red/black wire which runs to the fusebox is the rev counter wire yeah, you need to keep this. the mk3 loom will have a wire to this pin too, this is from the mk3 ecu and is not compatible with the mk2 clocks, so chop it out.

aye you chop out the purple wire, and just leave the vac hose connected up to the clocks as per std mk2 16v.

The blue wire is the alternator charge wire, but its to F/3 the reason you're confuse is because on the mk2 the alternator wire is in the lighting loom, you'll see it neat to the battery +ve. on the mk3 this is moved to the engine loom, so in effect you now have 2 alternator wires! you can use either one. i use the mk3 one cos its neater, plus it uses much better waterproof connectors so no more corrosion damage.  the other plug is the reverse light switch
F/1 is a red wire, this is a starter motor live which is required for the MK3 ECU, so I think you might have got that one confused as well? F/4 is an earth, on the MK3 its for the speedo sensor. Reverse lights are to F/6 and F/7

the big connector block under the header tank is the radiator fan control unit, i bin this altogether and keep the mk2 fan wiring. the single pin sensor you mention is the after-run switch aye, i leave it disconnected.

this last plug is for a breather heater, which isnt fitted in the uk. follow the wires back from it and chop it out

[Simeon]

Thanks very much, I'll have a look at it when I get back from work

[Simeon]

Right, sorted (I hope) despite getting all those pins in plug F wrong not sure how I managed that one. Thanks very much John, great advice/guidance as always.

Just the immobiliser to sort now 

[rubjonny]

if you get all the loom for it dead easy to wire in, needs ign live, earth and a connection to ecu and diagnostic port. plugs will onlg go in the right place so those 2 cant mix up either. main thing is to get a matched immob unit + key/chip. once you have that can match any ecu to it using vag-com

[Simeon]

I bought the whole car so got all the matched bits. Haven't really looked at it yet, but when I glanced through the wires I thought there wasn't much that matched up to the loom .. will have a closer look later, trying to get the 'bay side sorted first so I can get the engine in