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1.8t conversion

Hi I have a 94 audi 80 coupe 2ltr 16v front wheel drive and I would like to fit a 1.8t out or a R reg passat, has anyone fitted one before inc using oem loom/ecu,
Any help would be much appreciated

Check I think that there is some project like this. There is a couple on Audifinns forum, but I can't really help you with the language

on motorgeek there is a thread by ruffiano saying how he did his 1.8t conversion.

Passat or Audi A4 will do the trick. You have to firgure out the intake line and intercooler placement. Most people do it front mount and I might have the right cooler for you PM me if you need it.

Other issue is the instruments cluster you will not be able to setup the rpm meter since 1.8t ECU uses CAN communication so i suggest look for instruments cluster as well from A4.

Done a couple of 1.8t's, most recently put an AUQ in my T4.

R-reg passat is one of the early ones, running me3, with cable throttle. This means you can't remap it yourself, and you can't fit cruise control for free, otherwise they're ok.

The 150bhp agu will go to 200bhp and drive really nicely, can recommend the jabbasport stage1 remap, transforms the car for 300.

I don't think a 1998 one will have canbus, but it's nowt to worry about. Gofors is right about the rev counter, but the issue is the coil signal - your car probably has a single coil feeding the rev counter, 1.8t has coil on plug. So you need to combine the signal from these 4 coils into 1 signal for your rev counter, this can be done using a diode bridge, there is a plan on clubgit but I've not done one yet.

The wiring isn't too hard, took me about 8 days to do the van, but that was a pretty complex job. Basically start off with all of the wiring from about the handbrake forwards in the donor car and remove what you don't need. Along the way I modified it so the new engine loom plugged into the van fuseboard and the new clocks plugged into the van fuseboard. Neat, but very time consuming.

Immobiliser shouldn't be a problem

More on wiring:

I started off with the main loom from the handbrake forwards and threw away what I didn't need. There's a lot of stuff that you obviously don't need, like the comfort control module and the headlamp and indicator looms, but really you just need to sit down with the loom and the wiring diagram and a pair of wire cutters - there's so much needed that no one is going to be able to say 'use the red/blue/green wires and bin the rest'. This is what I started off with, spread it all out on the floor and got the missus to help me cut stuff out:

Once I'd cut out the stuff that obviously wasnt needed (HVAC control plug, lighting control plug, lighting wiring, convenience module, wiper wiring, etc), I worked through the 20v fuseboard one fuse at a time, looking up to see what it is and if I need it (I had a pretty clear idea of what I would be using from the van and didnt want to run two fuseboards). If it was something I didnt need, I removed the fuse and cut the wire going to it, then stripped out that wiring from the loom, back until it got to a junction. This left me with something like this:

I hung the wiring loom off the front of the engine, so I could have the diagnostics hooked up to it as I was removing stuff:

Assuming the your loom is similar to the agu and auq looms, there is a small plug on the ecu that goes to all the stuff on the block with a black multiplug that joins the loom on the block to the main loom, and a big plug on the ECU that mostly goes to the clocks/fuseboard, but also goes to the lambda and maf. The small plug stuff you can pretty much leave alone, that just stays on the block. I mounted the ECU on the bulkhead below where the two wiring looms come through, and used the original T4 gromit to push the 20v loom through. This shows the wiring that I'm left with which goes through the bulkhead:

The black multiplug (t16?) top left plugs onto the loom thats on the block, everything below the grommit goes through the bulkhead and plugs into the fuseboard, or directly into the clocks, the fuseholder goes onto the terminal 30(+) rail in the fuseboard, the yellow, green and brown fuseholders are all switched lives which were fused in the 20v fuseboard, I decided to keep these fused seperately, so got a fuse holder with a bus bar from a sharan/galaxy, which clips onto the side of the van fuseboard - may fit your audi too, and is powered by the terminal 15 rail. Fuse holder top left on galaxy board:

Bus bar modified for the blue (live with fuel pump) wiring and the black (live with ignition) fuses:

Its worth getting yourself some terminal tools for taking the plugs apart, obviously you will need decent wire strippers, soldering iron, multimeter, power probe, ample heatshrink, etc. Its worth getting a copy of elsawin, as the wiring diagrams are much easier to go through on a laptop where you can search them and click on a part to have it highlighted on the diagram, and obviously VCDS is invaluable, so you can tell if you've just broken it all by cutting a wire.

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