1988 Scala 1.8t agu conversion

[ant]

Engine being fitted:

14. Engine fitting.jpg

Engine strapped into place from the front to pull it forwards so that the rear mount could be fitted:

15. Engine fitting 1.jpg

Engine fixed in place with all 3 mounts! Couldnt resist putting the engine cover on, ha:

18. Engine fitting 4.jpg

[ant]

Once the engine was fitted i then started on the wiring, thanks to rubjohnny off the mk1 golf forum and his guide i had already worked out what needed to be done. I had previously labelled up the 1.8t engine harness and removed everything i wasnt going to need, i had also done the same with the scirocco engine harness and temp put them both in place to see how they would fit (the scirocco light harness was untouched):

20. Engine wiring fitting.jpg

I kept the 1.8t battery and its fuse box which fitted on top, below is a diagram which includes everything that it can come with as standard:

1.8t battery fuse box pic.jpg

I kept the alternator wiring (S177) and the power to the interior fuse box relay panel (S176) from the 1.8t as they where in better condition than the sciroccos. I also kept the wiring from the 1.8t battery fuse box to the radiator sensor and to the coolant fan, I swopped the scirocco mk2 radiator sensor with the one from the 1.8t’s which was a direct replacement and would then fit the 1.8t plug. With the standard wiring from the sensor to the fan I cut the plug off the end so it was ready to join to a new slim line fan I was planning on using. This was the best option as it would allow for the fan to keep running even when the ignition was off like the audi a3 would intend to do. All other wiring was removed (S163 and S162) and spare fuses taken out (S179 and S178).

Below is a pic of the rear of the sciroccos CE1 fuse box and what they are and i will then list what i kept and where i wired in the 1.8t harness:

CE1 Fuse box rear pic.jpg

A (Blue – 28 pin) Instrument cluster wiring harness
B (Red 28 pin) Instrument cluster wiring harness (position 5 open)
C (Yellow – 22 pin) Engine compartment/engine management, left side (position 10 open)
D (White 29 pin) Engine compartment/wiper motor wiring harness, right (position 6, 10, 14, 18, 27, 28 open)
E (Black 18 pin) Rear wiring harness (position 17 open)
G (N/A) 1 pin with 10 individual circuits
H (Brown 6 pin) Air conditioning/coolant fan relay wiring harness
K (Neutral 5 pin) Seat belt warning system/coolant level wiring harness
L (Grey 4 pin) Horn wiring harness
L (Black 4 pin) Headlight/dimmer switch wiring harness
M (Black 2 pin) Steering column switch wiring harness
M (Black 2 pin) Headlight/dimmer switch wiring harness
N (Red 1 pin) Separately fused circuits (glow plug wiring harness)
P (Red 7 pin) 7 single point connectors for terminal 30 circuit
R (Green 2 pin) Open/ECU power supply relay

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1.8t coloured plugs to CE1 fusebox

Wiring table 1.jpg

Wiring table 2.jpg

Wiring notes and further info:

Coolant temp sensor

The MK4 4 pin coolant temp sensor will not work correctly with a MK1/2/3 dash temp gauge:

Fit a MK3 golf 1.8-2.0 8v 4 pin coolant temp sensor part number 357919501A or 6U0919501B, splicing the matching plug part number 357919754 to suit.

MK3 sensor pins:
1 - brn/blu - ecu sensor earth
2 - brn - dash sensor earth
3 - blu - ecu sensor feed
4 - yel/red - dash sensor feed

Late MK4 sensor pins:
1 - purple - dash sensor feed
2 - brown/white - dash sensor earth
3 - grey/yellow or blue - ecu sensor feed
4 - brown/blue - ecu sensor earth


Diagnostic port

1. Diagnostic port pin 7 (grey and white wire) to pin 19 on ecu (via orange plug pin 1 – solder together and shrink wrap).
2. Diagnostic port pin 16 (red and white) to ignition live feed G1 (with clutch)
3. Diagnostic port pin 4 (brown wire) to earth.
4. Diagnostic port pin 5 (brown wire) to earth.


Clutch sensor

1. First pin (white and red wire) to ecu pin (via green plug pin 4 – solder together and shrink wrap).
2. Second pin (yellow and black wire) to 10 amp fuse then to ignition live G1 (with diag port)


All of the wiring info above was taken from rubjohnnys thread and edited to fit my specific engine and car, i would not of been able to do it at all with out his info, the guy is a legend. see link for more deatils:
http://www.clubgti.com/showthread.php?2 ... dieselness!)



Hopefully the above will help some of you out that are thinking of doing the same, it really isnt that hard, just prepare and take time. Once all wiring was fitted in the bay it was taped together every 15cm to keep it together then removed and coverd with split conduit as i hate the tape that is normally used! It was then refitted and then connected up to the fusebox, i pushed the ecu connectors through the 2 big grommets in the bulk head so it could be housed on the tray under the passenger side of the dash.

[mark1gls]

Great build and looking good. Rubjonny does know his stuff and a very helpful chap, I think I've seen some of your question on the Mk1 golf forum as I'm on there as well.
Keep us updated.

[ant]

Great build and looking good. Rubjonny does know his stuff and a very helpful chap, I think I've seen some of your question on the Mk1 golf forum as I'm on there as well.
Keep us updated.

Hi yes recently asked a few questions regarding the speed sensor as I thought I wouldn't need it as not much on whether it puts you into limp mode or not. After getting it running and not wiring it in I'm now in limp mode, typical! In the process of finding one and fitting it to my clocks. Will post more updates soon.

[treefingers]

yeah best to leave the speed sensor in if you can.. taking a sensor out is like removing a limb as far as the ecu is concerned. the agu has less sensors to worry about though which is good

are you keeping standard clocks? i think you can get a splitter to use both a speed sensor and a speedo cable in the gearbox

you putting an lsd in?

are you using the 02j box?

nice progress btw

[ant]

yeah best to leave the speed sensor in if you can.. taking a sensor out is like removing a limb as far as the ecu is concerned. the agu has less sensors to worry about though which is good

are you keeping standard clocks? i think you can get a splitter to use both a speed sensor and a speedo cable in the gearbox

you putting an lsd in?

are you using the 02j box?

nice progress btw

Yeah I'm keeping the standard clocks, I've taken the sensor out the gearbox and fitted a golf mk2 1.3 cable to my clocks which gives me speed signal, I have just got hold of a vss from a mk2 golf with mfa and fitted it to my clocks which has worked as fault code has gone.

I have used the 02j box and haven't fitted lad, seen your project and looks great! Would you recommend fitting it?

Unfortunately mine is running worse since fitting vss, seems the more I replace sensor wise the more sensitive it is to the problem, massive power loss in all gears now, was fine for the 1st few days and progressively got worse, I'm thinking either fuel or boost leak related. Although I have checked for leaks several times.. When ever I put my foot down lightly or hard it really stutters, drops boost, powers up a tiny then repeats bizarre! Changed maf and n75 as when I unplugged them it ran better but no change with new ones so returned them.

[treefingers]

well i'd think it'd be n75 related if it's doing strange things on boost but you've tried that.. do you have a compressor? you can check for boost leaks really easily if you remove your air filter and make an adaptor to accept an air line then feed 20psi into the system. spray fairy liquid around clamps and connections and if you don't see bubbles you don't have any leaks. is it kangarooing when you give it power? it idles ok?

yeah i'd recommend the 02j over the standard 020 and also over the 02a. a strong setup with a vr6 clutch and abf flywheel. also the gear shifting mechanism is more advanced on the 02j over the 02a, it feels a lot more precise, and it's easy and cheap to shorten the shifting throw.

[ant]

well i'd think it'd be n75 related if it's doing strange things on boost but you've tried that.. do you have a compressor? you can check for boost leaks really easily if you remove your air filter and make an adaptor to accept an air line then feed 20psi into the system. spray fairy liquid around clamps and connections and if you don't see bubbles you don't have any leaks. is it kangarooing when you give it power? it idles ok?

yeah i'd recommend the 02j over the standard 020 and also over the 02a. a strong setup with a vr6 clutch and abf flywheel. also the gear shifting mechanism is more advanced on the 02j over the 02a, it feels a lot more precise, and it's easy and cheap to shorten the shifting throw.

Yeah it is kangarooing, idling totally fine though, will leak test it again at some point but is holding 30hg on tick over which is really good. Sorry didn't mean to say I changed n75 I tested that one but changed maf, resistance came back fine and blew through pipes to see if it was dead inside, maybe will try swopping with mates at weekend?

02j box is nice and smooth with its standard shifter, I mounted mine underneath but most people mount there's on the inside I think. Will hopefully get short shifter for it at some point..

You going to national meet, will be good to see another 1.8t there?!

[treefingers]

thats odd it sounds like your roc does what my car does.. idles ok then drives like a piece of shit when yoh give it gas.. really boggy and kangarooey but when i hold on the throttle it clears after about 5 seconds and the power comes on hard. i hope you manage to sort it!

what about o2 sensors? have you got both plugged in?

i've missed the meet twice already.. want to be there if i can this year!

[treefingers]

thats odd it sounds like your roc does what my car does.. idles ok then drives like a piece of shit when yoh give it gas.. really boggy and kangarooey but when i hold on the throttle it clears after about 5 seconds and the power comes on hard. i hope you manage to sort it!

what about o2 sensors? have you got both plugged in?

i've missed the meet twice already.. want to be there if i can this year!

for the 'box you can get an audi tt shift counterweight from audi for like £25 which will shorten the front/back throw, then to shorten the side to side throw you cut, shorten and reweld the other cable mounting point on the gearbox tower. :)

[bengould]

^ agu only has one o2 sensor.
Maf causes many problems on an agu, the whole map is dependant on it, as there is no manifold pressure sensor, and without correct data it just goes into limp mode. Did you swap it for a new genuine one or a second hand/repro one?

Ben.

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Treefingers mine doesn't clear just continues to do it and sounds a little like back fire as well as running real lean. Sounds good about shifter will look into it! If I figure it out I will let you know..

Thought i would upload a few photos of the wiring i removed from the audi, forgot to take pics of it made up as a new harness!

One harness with the coloured plugs and the other with the black t10a connector:

Wiring Removal 1.jpg

Obd port (definetly worth wiring in!):

Wiring Removal 2.jpg

Battery fuse box:

Wiring Removal 3.jpg

[ant]

^ agu only has one o2 sensor.
Maf causes many problems on an agu, the whole map is dependant on it, as there is no manifold pressure sensor, and without correct data it just goes into limp mode. Did you swap it for a new genuine one or a second hand/repro one?

Ben.

I swopped it for a new one from euro but not Bosch as they didn't have one, gunna swap it and the n75 with a mates at the weekend to see if any difference, I unplug them both and the car runs without the issues. Need to check barmotetric pressure sensor, not sure if that would affect it? Would have to be a major boost leak to cause these issues which I don't think I would of missed.

[bengould]

I wouldn't have thought the altitude sensor would make a massive difference unless you live quite high up. I would guess that if it gets a faulty signal it would default to sea level so wouldn't be that far out unless you live halfway up a mountain. I would try a genuine maf first. And clear fault codes if you have a cable to do so, residual codes can cause an issue even after you replace the faulty part. Also even a small boost leak can cause big issues with an agu, it relies solely on the maf to know how much air is going into the engine, if even a bit is getting out, the fuwlli g will be wrong.

Ben.