mk3 tdi swap build thread..pics inside!!

[lvnthehighlife]

the begining




front clip off



the ac sucked to take off..is there a special way to relieve the pressure from the ac or do you have to have it sucked out? and also i plan to do an ac delete kit for this setup. does anyone know where i can get a ac delete kit for the ahu tdi engine?



tank and lines removed


dropped the engine with the subframe



i also got the dash removed

thats it so far gonna start ordering parts and look for a good body to swap into..there is a vr6 jetta that i can get for cheap cuz it has a bad motor..the only questions i have is since the vr donor car im lookin at gettin is an automatic so do i just need the clutch pedal from the tdi and will the master for my clutch bolt up to the firewall as well...and i think i need vr6 manual driveshafts as i understand because the automatic vr wont bolt up to my tdi tranny and the tdi ones wont work in the vr body...and can i use the fuse panel/block inside the vr or do i use the tdi one?im not really looking to the whole wiring part when i get the donor..anything else im missing? ill keep things updated as i go along..any input will help

[lvnthehighlife]

and this is the car that will be getting the tdi engine


now since this car is an automatic if anyone knows what i need to do to convert it to manual would be very helpful before i start ripping into it. from what i understand i need to get vr6 manual axles cuz the automatic ones wont work on my tdi and my tdi ones wont work if i keep the 5 lug setup..if i could bolt the tdi subframe and axles up to the vr6 body but keep the all around disc brakes that would be great..thanks for the help

[MikkiJayne]

You could keep the 4-lug setup to save getting new axles. The TDI subframe as per that pic ^^ will just bolt straight in with everything attached. Swap the rear brakes for mk2 GTI rotors and your VR6 donor is back to 4-lug all round Alternatively if you do want to keep the 5-lug (which apparently does handle better) then you will need manual VR6 or GTI axles as you mentioned.

As far as swapping to manual, just use the shifter box from the TDI. The clutch master and pedal box should swap straight in.

For the wiring just use everything under the hood from the TDI and it should be almost plug and play. Use the TDI cluster and cluster harness too. The only gotcha I can think of is that there may be a lockout on the auto shifter to stop you starting it in gear, but you'll need to check the wiring diagrams for that. It may work the same as the clutch lockout that some cars had.

[lvnthehighlife]

thanks for the info man..i think im gonna go with the 5 lug setup though just cause its already there..im just gonna have to sell those rims and tires even though i just put 700+ into them..but i can invest that into the ahu..i plan on bigger turbo and methanol injection also..i have 1700 cash to dump in just parts right now..gonna start ordering soon!!

[lvnthehighlife]

started on the vr today..wasnt running when i got it. you have to jump the starter to start it and it drips coolant out from the block maybe, haven't found it yet im sure ill see where its coming from once the radiators off.and it is knocking pretty hard but auto tranny seems fine. so does that mean the ignition switch in the vr column is bad? can i use the tdi ignition switch? or what is the most probable cause of this? since i have to jump the starter to start it.

[MikkiJayne]

Ignition switch is likely. The TDI one is exactly the same, but I'd just buy a new OE one - they're cheap enough to not bother re-using an old one

[lvnthehighlife]

i got the vr out of the shell today without too many problems..id like to do an ac delete on the ahu. i heard you can just get a vr6 power steering pulley but then do you have to get a different belt as well?

and i noticed the brake resivor up front is different and has a big plug going to it with is connected to the main engine wiring harness.. so do i use the tdi brake resivor setup without that plug or whats the best thing to do..and heres the pic..notice the plug on the bottom right side of it

[lvnthehighlife]

o and does anyone know what that plug in in the firewall there on the left side where the heat shield is opened up is?

[MikkiJayne]

Thats the ABS block ^ I'd be inclined to keep that since IMO its a good safety feature. If you don't want it then swap in the (presumably non-ABS) braking system from the TDI.

Got a picture of the mystery connector?

[lvnthehighlife]

i started taking apart the fuel system to swap the tanks and i noticed the vr6 has a 4 prong connector while the tdi is a two prong..can i splice the tdi connector onto the vr6 one or do i need to take out the whole wiring and swap that too?

tdi one (tdi tank going in vr6 body)


vr6 plug in

[MikkiJayne]

Ah ok. The VR6 has an in-tank pump (outer two wires), plus the level sender (inner two). The TDI only has a sender so only two wires. Splice the two from the TDI connector in to the middle ones on the VR6 (match the colours), and just cover the other two up with tape.

Bear in mind the TDI uses the same relay for its glow plugs as the VR6 uses for its fuel pump, so the red/yellow wire will be live when the glow plugs are on hence why it needs taping up

[lvnthehighlife]

i got the diesel tank put in today and all the lines routed up. also got the interior out of the vr and started on the wiring.. what a mess it was in there. i ended up taking all the plugs out of the fuse block so i could maneuver things better. idk if that was a good idea or not. should i use the fuse block thats in the vr or should i use the one from the tdi? i got the main engine harness out but the other harness that goes to the auto tranny that was in there is connected to a bunch of wires that go to the left side by the hood popper and then run along the floor to the back of the car and i was wondering if i could just cut the wires that i know go to the tranny and leave the rest. idk what alot of the wires are that are in there but some connect to the main engine harness also that i have pulled out already. i hate wiring

i also found this under the dash. anyone know what it is? there is a brown wire that runs from it to a relay that goes under the center counsil by the e brake handle and there is a few open wires under there also that idk wat they are god i hate wiring

[MikkiJayne]

Thats an aftermarket remote keyless entry unit by the look of it. Or possibly an alarm, but it doesn't seem to have enough wires for that.

The VR6 and TDI fuseboxes are identical. I hope you labelled all the loose connectors when you took it out! All the main ones only go in one place, and the single wires with small coloured plugs all go in junction boxes with others of the same colour, but there are a few others which are important.

I have no idea about what to delete from the auto wiring. Maybe search the mk3 forum for auto>manual swap info? Its basically what you're doing as far as the wiring goes.

[lvnthehighlife]

made a big step in the project today,pulled both pedal clusters, got all the wiring pulled from the vr6 and tdi. put the tdi engine harness in the glx and started wiring it up..im still figuring it out but its goin better than i expected. one thing that is giving me some problems is the automatic tranny harness that was in the glx is tied into the main harness but none of them plug directly into the fuse block. the abs system also ties in with this should i just cut them? or wat you think? and i have never really got a straight answer on how to delete the ac. ive heard to use a vr6 water pump pulley and ive heard a power steering pulley as well. i have both so i wanna do this before the engine goes in. and where does the pulley go/take place of on the tdi engine?





waiting for parts to arrive


swapping out pedal cluster tomorrow after wiring.....hopefully

[MikkiJayne]

To delete the AC you need to change the water pump pulley from a V-belt one to a flat serp-belt one. The proper part number is 028121031E, which is different to the VR6 one. The VR6 pulley may work, but I don't know having never tried it. Its the same basic setup as the ABA, but the belt offset is different because of the wider timing belt.

You then run just the power steering off the V-belt pulley with a shorter belt.

[lvnthehighlife]

thanks alot man
i just ordered 2100 bux worth of parts i got the digi z 8 pin power module for 429$ i got an egr delete kit for 91$ upgraded turbo and clutch kit for 1367$ including gaskets for the turbo and i got pp250 nozzles for 322$... i still need an inline pump to help pump fuel to my injection pump so it dont have to work as hard.. fuel filter..and id like to get an inline filter..if anyone knows where to get those parts cheap or know of other parts that i would nees to go along with those upgrades that would be helpful..thank you

[lvnthehighlife]

started on cleaning the tranny


anyone know what this plug is? it enters the cabin in its own seperate litle hole away from all the other wiring (see second pic) i dont see anything out in the engine bay that it connects to


got the stick mounted

and pedals


i am still sorting wiring out..i hope it will start it will be ready for the engine once all my parts arrive. i noticed the vr6 auto steering column has a little lever on it for a cable to attach to by the key. wich went over to the shifter.im assuming its to make sure the car is in park before you can turn the key..can i still use that steering column? or do i have to use the tdi one..ok so to delete the ac i take a vr water pump pulley and put in in place of the tdi water pump pulley then get a differen belt? maybe im thinking to hard about that but i cant seem to figure it out i have all the pullies on the mk3 vr6

[lvnthehighlife]

got the new turbo, clutch, flywheel, and nozzles installed..all the engine components back together ready for the install..all i need is to get the downpipe custom fabricated cuz i cut the cat off then its ready to go in.
...

ok i still havent figured out what this wire is for and its really bugging me. its its own single wire that comes from the top of the firewall here.

and is really long and goes to this plug

there was no wire coming from that hole in my firewall on the tdi..it was plugged off from the factory. im guessing its just something for the vr6 but i cant find where it went to

[lvnthehighlife]

it is now a tdi!!
there are still a few problems that i am trying to work out though. i can not get it to crank over. i checked for power at the solenoid switch at the starter with key on and i got nothing but i jumped the starter and got it to crank over so everything is good there. im wondering since this was an auto if there is a safety switch somewhere? i swapped ignition switch from the tdi to the vr6 column because when i got the vr6 it wouldnt crank over either and i wanted to keep the vr key so i had to use the vr column. is there a way to test to see if the ignition switch is good? it worked in the tdi so i dont see why it wouldnt work now. im really hoping i can get all this figured out. this wiring **** is really starting to piss me off and its holding me back alot

[lvnthehighlife]

i can get the engine to crank over by jumping it. i got power after the ignition switch as well when the key is on position. im wondering if anyone knows what one of these auto trans harness plugs is the one for the park/neutral safety switch...which is maybe causing it to not start. and should i leave that harness in there? it would be a mess to follow into the cab to delete it.


and there is also this vacuum line that comes from in between the two coolant lines that im not to sure where it is supposed to go to

and what is this device for? where are the lines supposed to go to?


this is the only wire that i have not found a home for yet in the engine bay. anyone know what it is? heres where the wire taps into



i am pretty sure the vacuum lines for this are mounted correctly. i just dont know what it is or what its for. any ideas?

im not sure which vacuum line is supposed to go to this either there is two ports on it and one is plugged in but idk what line goes to the other one


i wired up the fuel gauge from the tdi to the vr6 so i could use the tdi plug since i put in the tdi tank, and it is not reading on my cluster when the key is on. and there is fuel in the tank. also the odometer and clock which is normally on turns off once the key is in the on position.the dash is not in yet but i got pretty much everything plugged in, this wiring has really got me frustrated any help would be much appreciated..i really wanna get this thing on the road.
i have the radiator and everything hooked up..i just want to get all this stuff buttoned up before i try to start it.

[lvnthehighlife]

i still havent figured out wats causing it not to crank over but i did also installed a external fuel/lift pump on the car.
i was wondering where to run the power wire to so that it gets 12v only when the car is running so that the pump is pumping only when the inj pump is pumping.

[lvnthehighlife]

ok well i unplugged the alarm module thinking this was causing my no start problems (read on another forum that is an issue sometimes) nothing happened. but when i plugged it back in and hooked up the battery the alarm goes off and wont stop. ive tried the key in the door and the key in the ignition. and nothing works now like it used to..the power locks dont work now when they did before, the windows and cluster also dont work which i had working before

[mafosta]

If I'd seen this from the beginning I would have advised that you also transfer the whole harness from the old TDi unto the new car

[lvnthehighlife]

i ended up starting all over.pulled the harness all apart again and traced down the auto tranny harness back to the tcm and remove it.i kept the abs though. with that out of the equation i started plugging wires back into the fuseblock. now that i have done all the wiring again for the second time it still wont ****ing start. i get nothing showing on the cluster except for the glow plug light and battery light and that stuff, but no odometer or clock.