OEM MK4 management wiring => Mk1/2/3 harness install FAQ (Now with added dieselness!)

Oh sh*t, ur right my bad

 

Hello guys! Im still unable to turn on my seat leon cupra 4 vr6 24v BDE engine in a mk4 golf, all 3 stop lights are constant on without the brake pedal being pressed nor the handbrake on thats one issue ive always had, thats one issue.
Ive already inverted the pin on the brown and orange plugs but theres a pin or two that stay unconnected and then I trimmed the white plug to fit in the green and also 1 pin in the 6 position gets missmached/unconnected...
Also the black plug doesnt have nothing in the car to plug it to...
ive connected a ob2 code reader and im getting the error 1338 wich reads Camshaft position sensor. bank1 open Circ./short to B+..
Also I dont have front lights
Any ideas?

 

ok thanks Jonny! and another thing, when I connect the violet wire (pin4) from T10a to t14 the gas level is showing on the oil temp gauge... this was supose to be coolant temp to dash right? what im I doing wrong?

 

hello again everyone! my 2001 vr6 24v is still not starting... went through all earth points I could find, gave them a cleaning and tightning check up, now aparentely I dont have any error codes coming up but going through the wiring again I realised that in the t10a to t14a conections the wire in t10 pin8 (black /purple) cant go on the t14 pin 8 because here is the red/purple that needs to conect to T10 pin5 also red/purple... so where should I connect it to?

 

Ive also changed the brake pedal sensor but stop light keep lightning up when I polug the batery...and found a long wire with a t12 plug sort of stuck under the back seat near gas tank/pump that didnt seem to belong there or connect to anything near..

 

stop ligth could be constant on because of the black plug in the plenum chamber not being connected to anything?

 

Hi again guys, Ive been driving mk3 for quite a few time now after I swapped it, and oh boy how I missed it. Anyways I have some more questions regarding 1.8T swap.

So first thing, my coolant temp. gauge seems to never go above 80 deg. C and at that point it turns fans ON. I find this really weird because it really takes a long time driving to go above 70 deg. C. Ive swapped out 2 mk3 temp. sensors i have and both seem to do the same thing. Could this be compatibility issue or something else, I just don't want to cook my motor.
Second, when accelerating 90% of the time I get boost cut off at around 3.2k RPM, with the exception of doing a pull in 1st gear where sometimes it doesn't cut off and sometimes it does. All the valves and stuff are still on the motor, I haven't deleted any of the stuff so could it be n75 or air leak somewhere at IC piping?
Final thing is, I cant connect to OBD even tho I wired up everything as per guide, so I cant see any of the faults regarding my first 2 questions.

P.S. idk if I said it already, but I drove the donor car 400km before swapping 1.8T into mk3 so I know everything was working perfectly before.

 

Its dbc/AGU engine code.
Ive solved OBD problem, looks like somehow one wire was snapped.
Faults I get are:
- Airbag ( don't have it )
- Charcoal canister ( don't have it )
- ABS ( don't have it )
- Internal ROM Error ( P0605 )
- Fuel Pump Relay something something ( didn't catch that sorry )
I still cant find boost issue, do u maybe have some suggestions? I tried different fuel pressure valve, tried to bypass n75, checked all vacuum lines and intercooler hoses all good on that side.
Seems like im going in circles and cant find solution what will probably be a easy fix or smth small, thank you in advance for your reply's i really appreciate it, since Im used to NA cars and this is my first turbo

 

Yeah I guess ROM code was either before there or happened when I gave my ECU to get immo off, but I don't think it affects boost problem I'm having. Fuel relay code could be because ever since I got the mk3 ( for 3 years now ), fuel pump is always on after I turn ignition on, so it effectively constantly pushes fuel. Fuel pump I have is 2.0 8v/3bar which should be okay regarding fuel pressure ( if somehow it didn't go bad meanwhile since I bought new one 6 months ago ). Could some sensor be affecting boost? Last thing I can think of is that somehow turbo housing cracked and its leaking, so I cant build enough boost. But then I wouldn't be able to do a "good" pull when car just lets me rip it 1st and 2nd... One more thing, after that rare moment of turbo spooling good and giving me full power, engine goes in some kind of state where it limps around and I get barely any power to drive, it stays like that for some short period of time than comes back to life, ofc limited to 3k rpms.

 

Hi Jonny

Have a 90s mk2 big bumper getting 1.8t aum swap.
Ce2 factory air con

there is a 2pin plug which has 1x wire go to the digifant 2 ecu pin#16 green and the other one this plug wasn’t connected up but is a blue wire.
Is it just a matter of connecting 1x green mk2 wire to t10/7 orange or do I need to connect something else also? Other a/c wire is blue/red t10/8.

How would you connect it up to make it work as per factory. Will be putting a new mk3 air con pump and unpinning the plug to the compressor to suit the mk3 style pump. A/c is r12 gas so was also getting all new air con service items. What about the high/ low pressure switches can we leave these as is or need to run a newer style switches?

 

Hey, First off, thank you for the great and informative thread.

I got a question regarding the t14a plug for CE2,


5 | red/pur | Z/1 ECU relay pin 87 (diesel) | Fuel pump live for injectors, diesel pump on non-PD engines |

Should i bin this wire for a 20vt aum swap or should i combine it with blk/pur from pin 8 to z/1? Al the threads i find about this refer to this as a live for injectors ( but it says diesels only) aswell.

Thanks in advance!