DX to ABF engine wiring loom conversion

3. red/yel - dash temp sensor ….. Bin?

7. 2x oil pressure switches, and mfa oil temp sender…… Keep or bin? confusing as i believe i have some sensors relating to oil and coolant which run through my mk1 loom.

Off the top of my head i think the mk1 loom/fuse box has red/yellow to coolant temp which originally was spliced to a brown/white wire, purple/black to oil sensor and i think black/yellow to oil sensor
Cheers.

hi matey,

i decided to plug things in today just to see if i am on the right track and i have a feeling ive gone wrong somewhere along the line..

What i did was plug things in and the car spins over fine but no fuel pump or anything. i unplugged the ecu connector and went to check for any lives with a test light to the ecu pins, the fuel pump kicked in when i put the test light to the yellow/blue wire on the ecu plug. i assumed it was because i hadnt connected an earth and it kicked in as the earth from the test light supplied it. I earthed  the thick brown wire near the ecu plug to the body and the fuel pump kicked in again but stays live all the time and my dash lights are on with the key removed..

I tried removing the earth again and it now still works and does the above with no earth.

Any ideas as to what i've done wrong. maybe ive bitten off more than i can chew :-s

Also if i unplug the connector which goes from the ignition key to the back of my fusebox (H1) it stops the constant ignition live. ie if i turn the key off the dash lights go off, if i turn the key on they come back on, however, it wont turn over now as the starter wire is unplugged… If i unplug all of the ecu connectors from the mk3 loom and plug H1 back in the dash lights are back on constantly again.

I got my head underneath and it looks like the back of the key fob has identical wires spliced together…. once set goes towards the mk1 fuse box and the other to the other H1 connector and into the mk2 fuse box……??

When the earth and power wires to the battery are on the battery the fuel pump kicks in with the ignition off.. There is a red power wire which comes from the mk2 fuse box direct to the battery, this kills the mk1 fuse box when unplugged so i'm guessing this is the main power feed. What is going on  Fancy taking over where i left off HAHA

Man cannot be defeated by a few poxy wires!!

Maybe if you could help me complete this little word sheet I've made it would narrow things down and get shut of some wires that are not in use but here to confuse things ;-) I've managed to get hold of a wiring diagram so I've done what I think is right… Tell me if I'm wrong or tell me where to put/splice the wires to if you know. Thanks a million.

ok next step is pull all the relays out of the mk2 fusebox, the only ones you need are the ecu #30 in slot 3 and fuel pump relay 67,80 or 167 in slot 12.

http://www.clubgti.co.uk/forum/showthread.php?t=219775

the yel/blue wire is an earth trigger from the ecu to tell the pump relay when to fire, so dont earth it as you found out
you want to keep this wire, splice it back as it was! this is a great way to tell if the ecu is workign, if no prime then it no power up. dont be confused by the fact it will only prime once though! after the first turn of the key the ecu wont prime the pump again for a while. but the pump should always run while the car is cranking on the starter.

keep the ecu temp sensor wires, the ecu needs them so it knows how hot the engine is! pin 27 is the ISV wire, keep!

oil/water sensor wires you'll probably be using the ones on the mk1 loom, as i doubt the last guy spliced the sensor wires into the mk1 cluster in the mk2 engine loom.

finally lambda you need to fit but it will run ok without if you havent got the boss welded in yet, so that can be done later once the car is running

Howdy,

Right, i think i've made a lot of progress tonight. I've cut out unwanted wires and shorted some wires which had no reason to be so long. It now looks more managable and should stop confusing things when its in the engine bay getting resized. I have kept all of the wire just incase i need to add a little more length in places but i doubt i will.

Ok… as i was cleaing the loom up i came across a few wires which i wasnt sure about. Maybe you might know??

Here goes:

1.Pin 7 on the ecu plug (red wire) is for the starter motor feed? Can i just remove a bit of insulation from the starter motor wire (thick red/black from my mk2 loom) and wrap the red wire (pin 7) around it and solder? so basically can i splice it directly to it?

2. From pin 8 there is a green/red wire for the ignition?… Can this be cut away from the plug connector (with black and brown wires) and put directly to the green/white wire on the coil.

3.There is a Black/white wire from the round engine loom connector. I believe this goes to pin 1….. Is this for an engine control relay or something? what do i do with this, will this go to my engine relay or am i binning it?

4. Plug F to the fuse box with the thick black/red starter wire……. Which wire do i keep from this plug as there is only the starter wire in use a it had WUR and 5th injector for the k-jet before… I pressuming i can cut these wires out and just leave the starter wire on its own in this plug…?

5. Again… on the round engine loom connector there is think black wires (pin 15?)… This is spliced to a thick black wire down to connector G1 at the fuse box end. I have left them spliced together but what are they for and do i need them…. If memory serves the thick black wire was connected to the mk3 ignition connector….. (The one with the green/red, black and brown) what do i do with the thick black wire?

I think thats all the questions for tonight :-)

Btw, i took all of the relays out of the mk2 fuse box and the ignition is still on with no key in the ignition… Rather confusing to say the least.

Oh just one more question... Does it have to be a 2.0 16v for the diagnostic port. Been trying to get one. Maybe another smaller engined golf has one?

1. yep this is what i do on my looms now. factory this would run to a spade on the lighting loom but its just 1 more thing to confusle my costomers! KISS

2. this is coil trigger, goes to pin 6 of the tci. see all the masses of information i wrote about converting it to use mk1/2 coil

3. ign live feed for isv and the breather heater. this needs to be kept for the isv! you can cut out the breather heater wiring. look at the other side of the roudn plug and follow the wire from pin 1. it should run to the isv and split off to the breather heater, trace it to the plug and remove. the breather heater plug has a black and a brown wire, it runs round back of engien near to the TPS and idle switch. its not used on euro abf and it can short out round the back and blow isv fuse

4. plug F has trigger for starter, reverse wires, alternator blue wire and lambda probe earth. you probably wont need any wires in this except the lambda earth, depending where your starter gets its trigger from? on your car is it from the mk1 fusebox or mk2? the reverse wires run to the lighting loom in the mk1 so this is probably where its fed from in your car. if you decide to keep the mk2 F then cut the brown wire for the lambda off and earth it somewhere else. if it was me id keep mk3 wire and use a mk3 golf 1.8-2.0 8v starter motor so you can use the nice square clippy trigger plug rather than the dodgy old mk1/2 spade which can corrode and fall off. plus mk3 starters are a bit beefty

5. think you got wires mixed up here. pin 15 on round plug is for fuel injector #1. the black wire from the coil to the round plug goes to pin 5 and is for the speedo sensor ign live feed. this is the plug with black, brown and blue/white wires. if you dont need this you can cut it out and remove all the wires for it. only required for dash with electronic speedo

any mk3 golf post-96 has the diagnostics port you need. pre-96 have too but its older 2x2 port. most vag-com ports use the later 16 pin plug so its easier to use that.

with the fusebox live issue unplug all the connectors from the back of the mk2 fusebox. if it still does it then its a problem with the mk1 wiring or the way the mk2 wires are spliced to the mk1 loom. either way trace all the wires to the back of the mk2 fusebox back to where they go, hopefully you'll spot the error.

Hi mate

Good news, i have sourced a VAG com port for £5. It comes with all of the wires complete with the connectors on the end. The chap also said i can have the lambda sensors Result!

Ok, tonight i have had a play around under the dash to try and figure out why i had a permenant ignition live to my clocks etc. Took me a while but i figured it out…….. There was a fuse in slot 19 on the mk2 fuse box which wasn't there before. I remembered putting the fuses in so i must have mixed two fuses up at some point. Anyway, as soon as i removed it it solved the problem. Great!

I have also soldered the red starter wire from the mk3 loom into the red/black thick starter motor wire on my mk2 loom. I have done it this way as the starter motor fitted to my car is all but a few months old so it would be daft to go shopping for a mk2 starter or something and spend extra money that i dont have. Good advice tho, i will keep it in mind incase my starter goes boom. Nice!

Question time ;-)

1.Right, so i now know this black/white wire is for the Idle Air Control Valve Ignition Live…… But where does it go? I must have either chopped it by mistake or i am missing the point? (Picks to follow) Does it connect to the fuse box or direct to the IACV or are you saying this also needs to be spliced to an ignition live in the loom, somewhere like ecu pin 38 black/white wire which goes to the fusebox connector G2?

2. Just to make sure the Grey/white wire from the imobilizer box goes to the grey/white wire with the brown end (Diagnostic wire) I have no female connector for this if this is the case or any connector for that matter on my imob box so do i cut and solder?

3. I have soldered the Black wire from the imob box to the black/brown wire which is ignition live from ecu pin 9. I have traced this  near the fuse box end and spliced it down there…. Correct?

4. I have a brown wire which is obviously an earth. This is coming from the Lambda Prob. (red/white, yellow, white and brown wire) Shall i put a ring connector to this and earth it to the body or engine?

I think that will do for this evening…. I'm sure i will have some more question to annoy you with tomorrow ;-) Bear with me tho, don't bang you head against the desk just yet, We are getting there slowly but surly and i have learnt so much!

1. Black/white (ignition live for idle air)
2. Thick black wire. (speedo sensor?) Bin?
3. The two grey/white wires to e joined… Diagnostic and imob box.

Oh one more thing…

Relays…

I have a fuel pump relay but not sure about ECU relay.

I have this one if it's any use while I buy one.

1. it needs ign live of some kind, it runs to G2/4. this also powers ecu pin 38, you can splice it to coil live G1/4 if you dont have G2/4 for some reason?

2. factory the ecu grey/white has a brown plug, this plugs into the matchign brown plug on immob box. then wire from immob box goes to diagnostics jumper block above the ecu. you can just splice em all together if you like! vw used plugs so that you could split engien loom from interior loom. if u solder, just means more plugs to drag thru the hole in the firewall!

3. any ign live feed will be fine, i would have used g1 or g2/4 but it makes no odds

4. earth it wherever is easiest dude, you could use chassis or ecu/tci earth. wherever is easy.


thick black is probably the old coil live right? running from g1/4? can splice your black/white to this if g2/4 isnt available. otherwise bin.

relay i think is a fuel one, what are all the pins? the ecu relay is somethign like £13 from vw so may as well buy new

Right… Massive help!!

Think i've just about done all i can in the house, i think the next step is to try it in the car.

I think all i need to do is sort out the ecu earth. I might extend the wire slightly and connect it direct to the battery.

I need to sort out the ignition with the red/green wire. not quite got my head around it yet but then again i have only skim read your info so far.

I must get an ecu relay organised. I will order one through work tomorrow.

My super ecu chip arrived today but i thought it may be a good idea to fit it after ive driven the car or at least got it running. I read the guys feed back and someone bought one of his chips a while ago for a toyota or something and the car stopped running once fitted, he swapped it over with the original and it ran again. This could prevent any extra head scratching incase it happens to me and i dont know about it ;-O I'd like to feel the "benefits" also.

Hopefully the OBD connector will be here tomorrow so i'll wire that beast in and take it from there.

Rubjonny, let me just say you've been absolutely ace so far and i couldnt have done this without you. Cheers mate. i'll get the loom fitted and be in touch with no doubt loads more question hahaha.

haha, told you it would be long.

Dont suppose anyone has an ABF air pipe or anything forsale as i done seem to have an airflow sensor or a hole for one in my pipe, it is also missing the hole for the idle air control valve and i seem to have lost the rubber thats sits in the manifold which the idle control valve sits in

Oh dear.

the IAT sensor fits in the air box on the abf so thats why you dont have one, easiest thign is get a code filter specifically for abf with a sensor hole. you can just kinda stuff the sensor near the cone filter for now and it'll be ok. on my mates mk2 we shoved it in the front of the airbox hole till we got proper SEAT ABF airbox

same goes for the ISV, it runs to the air box. easy fix for this put a mini breather filter on the end of the isv

isv rubber is cheap from vw:
037 133 374 e - isv seal - 2.97+VAT

may as well get ecu relay too:
165 906 381 - ecu relay #30 - 12.33+VAT

Howdy,

I received the OBD port today. Not too sure on the wiring as yet. From the OBD plug I have 16 pins (obviously) in pin 4 there is a brown wire, pin 7 grey white, pin 15 yellow 16 red/white.

The yellow and grey/white go down to a white plug (2 pin), red/white down to a blue plug (fuse box?) brown to blue plug, there is a grey wire wire with a single brown plug which is snipped at the other end so goes no where.

What do I solder my grey vag com wire to?

Cheers

cut the red/white wire off the green plug, then splice this and the brown wire to your ciggy lighter. the grey/white wire is the diagnostics, this runs to the immobiliser box wire. factory you would have a jumper block to plug the vag-com port and immob box wires into to connect them, but you can splice direct if you like.

ignore the yellow wire its not required

I'll have a blast at this today then.

I ordered a relay and I.A.C.V seal yesterday so I should have them Monday. I'm still fishing around for the air temp sensor, they're £30+ the dreaded from VW. Not sure if I'd get one cheaper elsewhere. Could do with a part number.

I've been offered an 8v sensor but I dont think it's the same.

Anyway… I'm off to The Derv Dr to have my fuel pump set up on my Transporter T4 so when I get back I'll have a look.

Cheers

8v sensor is same from certain models, if its a 2 pin one you should be fine. also fitted to some diesels and a fair few others.

part number is 028 906 081

it'll run without but it'll be better once you get one