# THE (hopefully) ULTIMATE GUIDE to the Mk1 VR6 SWAP THREAD!!!



## jetta trek (Nov 11, 2007)

Just as the title says, this is for swapping the Mk3 AAA 2.8 VR6 engine and 02A transmission into the Mk1 cassis.


*Im going to write this in the hope that it can become a sticky for everyone. Ill add bit and pieces over time, so keep checking back. 
*

Ill do my best to cover all available options on how to do this based off of my experience and collective knowledge of the other members who have helped me along the way. 

The information provided is here for everyone to use. Comments, suggestions and corrections to possible incorrect information are always welcome. 

I plan on breaking this down in sections in no particular order, but will do my best not to go all over the place. :laugh:



RESOURCES 

Here’s a list of all places that you will probably have to check out to get this project done. 

NOTE: I will add/edit and links that need to be provided you PM me. 

I have also provided links to my Dropbox with the full Mk3 and Mk1 Bentley manuals, so no more scourging the internet for them

1: (Electrical Diagrams) 

http://www.a2resource.com 

2: (SAI delete) 
  https://sites.google.com/site/stoyn...moving-the-sai-secondary-air-injection-system

3: (VR6 conversion kit) 

http://shop.eurowise.com/category-s/278.htm


4: (Mk3 Bentley Manual)

https://www.dropbox.com/s/nk1jwtkpyqihqk1/MKIII Bentley Manual.pdf?dl=0

5: (Mk1 Bentley Manual)

https://www.dropbox.com/s/ivnvu5iif4vg15q/Mk1 Bently.pdf?dl=0

6: (Mk1 Parts Resources) 

http://www.autohausaz.com/index.html

https://www.rockauto.com

7: (Cabriolet info) 
http://www.cabby-info.com

NOTE: While this site is primarily focused around cabriolets, It has a LOT of good info that can be used on a standard Mk1 





DONOR CAR 

This writeup is talking about the Mk3 VW’s. While the Mk4 VR6 can be used in a Mk1, there are different procedures that have to be followed that I am not familiar with. 

Here are a few notes to be taken…….

1: Find a car that hasn't been gutted yet. Its a lot easier to sell off what you don't need then to scavenge for what you do. 

2: If you are doing this project on a budget, there are a few things that can be done to help keep some hard earned clams in the bank. 

Use the stock radiator, some cutting will have to be done, but it fits well. 

Use the stock exhaust manifold / down pipe. It will have to be cut short and at an angle to clear the steering rack, but works just fine. 

3: Don't spend any money on aftermarket performance mods unless your 100% sure that it’s the route you want and can afford to go. By the way, that little car is going to be a little rocket ship. 

4: Here is a list of everything you will want to pull off of your donor……

Engine

Transmission

Radiator

ECU

Full engine harness (take as much wiring as you can, you can strip off what you don't need later) 

Cable shift box 

Fuse box

All coolant lines

Oxygen (O2) sensors 

Guage cluster (if you want to go that route, I will show how to get everything hooked up) 

Guage cluster harness

This will get you going for now. There may be a stray nut or bolt you will have to get, but this covers 99.9% of what you will have to take.


MOTOR MOUNTS :heart: 

As much as I condone making your own parts, Skip the headache and just go buy the Eurowise kit. http://eurowise.com/shop/index.php?main_page=product_info&cPath=1_841_853&products_id=11

You will be very happy that you did. 

The guys at the shop are VERY helpful and are willing to answer any and or all questions about their kit that you may have. 


WIRING AND STUFF :what:

This is the Mk3 fuse box showing only the harness point that are needed to make everything work including the speedo cluster. 

I have blanked out everything that is not needed in an effort to make this simpler to read. 

Here it the breakdown of whats on here.......

*
D	Miscellaneous Equipment (GREEN)
D/08 Auto. Trans. Shift Lock Control Module, Interlock Relay, Malfunction Indicator Switch, E/2 (cluster power for A3)	Main Fusebox Start/Run Power	(Black)

E	Instrument Wiring Harness (GREEN)
E/02	D/11 or D/8 (Start/Run Power for cluster, 1991+ Corrado, Passat, all other models), Immobilizer Module	U2/1	(Black)

(NOTE) YOU WILL NEED TO JUMPER THESE TWO TERMINALS ABOVE TO GET YOUR MK3 GUAGE CLUSTER TO WORK!!!!!!!



G1	Engine Compartment/Management, Right Side (WHITE)
G1/03	ECU- Fuel Pump Relay Turn-On (gas), Engine Temp Sender (Pre-heat, diesel), thermoswitch for preheat (carb)	Fuel Pump Relay Power	(Red/Yellow) (gas engines), 

G1/04	Ignition Coil Pin 15 (Digifant and CIS-E), Motronic ECU Pin 14 and coil power stage Pin 1(Motronic), Altitude Correction and Fuel Cut-Off Valves (diesel)	Main Fusebox Start/Run Power	(Black) (gas)
G1/05	Ground on Cylinder Head	Ground (for gauges/warning lights)	(Brown/White)

G1/08	Heated Oxygen Sensor Power	Fuel Pump Relay Output, Fuse 18	(Red/White)

G1/09	MIL Lamp from ECU (TDI)	Gauge Cluster MIL Light	(Yellow/White)

G1/10	Digifant/Digijet ECU Power, Injector Power (1989 only), ISV Power (G60 only)	Digifant ECU Relay Output	(Black/Yellow)

G1/11	Vehicle Speed Sensor	Gauge Cluster	(White/Blue)

G1/12	Ignition Coil Pin 1 (all Mk2, most others '90 only), ECU tach signal (all 91+ except Mk2)	Tachometer	(Red/Black) (coil) or (Green/Black) (ECU)


G2	Engine Compartment/Management, Right Side (WHITE)
G2/01	Oil Temperature Sender	Gauge Cluster (MFA)	(Green/Black)

G2/03	Coolant Temperature Sending Unit	Coolant Gauge	(Yellow/Red)

G2/04	Knock Control Unit, Oxygen Control Unit, and Throttle Switches (CIS-E), automatic choke and overrun cutoff valve (carb), Heated O2 Sensor (Digijet), Fuel Pump After-Run Control Unit and Crankcase Ventilation Heater (G60)	Main Fusebox Start/Run Power, Fuse 15	(White) (carb), (Black) (all others)

G2/05	MIL Light from Motronic ECU (Passat VR6)	Glow Plug Relay Pin 9	(Yellow/White)

G2/06	-	Fuel Pump Relay Pin 5	-

G2/08	Secondary Air Injection Pump Power, EVAP Canister Valve Power (VR6)	Fuel Pump Relay Output	(Red/Blue)

G2/09	VR6/ABA Motronic ECU (Fuel Pump Input)	Fuel Pump Relay Input	(Red)

G2/10	High Oil Pressure Switch	Oil Pressure Warning Unit	(Yellow)

G2/11	Low Oil Pressure Switch	Oil Pressure Warning Unit	(Blue/Black)

G2/12	-	(no pin)	-




H1	Steering Column Wiring Harness (RED)
H1/04	Ignition Switch Start/Run Power	Main Fusebox Start/Run Power	(Black)

H1/07	Ignition Switch Key-in Power for Seatbelt Relay, Automatic Shoulder Belt Control Module, Radio	Seatbelt Warning Relay Pin 5	(Brown/Red)


M	Fuel Tank Wiring Harness (BLACK)
M/01	Fuel Pumps Ground	Main Fusebox Ground	(Brown)

M/02	Fuel Pumps Power	Fuel Pump Relay Output, Fuse 18	(Red/Yellow)

MISC.

Y/03	Battery Positive	Main Fusebox Battery Power	(RED)


-Z2	Battery Ground	Main Fusebox Ground	(BROWN)


*




....and what the harness should have on it at the end......




USER SUBMISSION :wave:

This will be a spot dedicated to user who submit good useful info. So please, PM me or submit to the thread. The more detailed on how to do, gather, perform, finish and find the info you submit, the better for all. 




CasuallyWreckless said:


> Mk3 ignition switch bolts right in too, may as well grab that and the harness for it.. Less saidering down the line. You can use the mk3 wiper motor with simple modifications as well. Eurowise now sells a nice drop in rad for 100$ as well....





mkdeucevr6 said:


> I'm almost done with my vr6 83 jetta and did buy the eurowise radiator (and stage one plus kit) however it does not fit properly do to having four headlights it's about an inch to wide to sit between the lights. When I find a reasonable solution I'll post it.





CasuallyWreckless said:


> ... A 16v scirocco throttle cable is a direct fit to the mk1 pedal and to the mk3 throttle body....


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## CasuallyWreckless (Aug 27, 2007)

Mk3 ignition switch bolts right in too, may as well grab that and the harness for it.. Less saidering down the line. You can use the mk3 wiper motor with simple modifications as well. Eurowise now sells a nice drop in rad for 100$ as well. I also noticed you didn't mention the clutch master or slave assuming your going to be using the cable actuator and either a crx cable or the eurovan one?


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## jetta trek (Nov 11, 2007)

CasuallyWreckless said:


> Mk3 ignition switch bolts right in too, may as well grab that and the harness for it.. Less saidering down the line. You can use the mk3 wiper motor with simple modifications as well. Eurowise now sells a nice drop in rad for 100$ as well. I also noticed you didn't mention the clutch master or slave assuming your going to be using the cable actuator and either a crx cable or the eurovan one?



Thanks for the info, This is what I hope to see more of. 

This is a add as I gather info thread. So what you see so far is just the tip. It would take me a LONG time if I just sat and added stuff in. Also this way, all of us here on the forum can submit their ideas and knowledge. I will add all good info to the thread with credit given where due.

Hows this, I will add a section at the bottom of the thread with ideas from the users. That way everything stays together. The more detailed the info, the better for all.


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## CasuallyWreckless (Aug 27, 2007)

:thumbup: moving forward lmk if you have any questions. I'm assuming your going to be using a eurowise kit and converting to ce2?


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## jetta trek (Nov 11, 2007)

almost. If you haven't, check out my build thread this is based off of. 

http://forums.vwvortex.com/showthread.php?6112144-Vr6-into-86-cabrio


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## CasuallyWreckless (Aug 27, 2007)

jetta trek said:


> almost. If you haven't, check out my build thread this is based off of.
> 
> http://forums.vwvortex.com/showthread.php?6112144-Vr6-into-86-cabrio



Very nice, I did a quick read through. A 16v scirocco throttle cable is a direct fit to the mk1 pedal and to the mk3 throttlebody. It is my recommendation that you do as much as you can while the motor is out as well. It comes out to be about 900$ to do clutch, hg, chains all cooling components. There's a lottt more avail to buy since they first came out with this kit. If you have the money you could literally have one of these built in a weekend.

Have you ever considered running an inline small high volume filter under the car then you can just run the fuel lines straight to the fuel rail


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## mkdeucevr6 (Nov 28, 2008)

I'm almost done with my vr6 83 jetta and did buy the eurowise radiator (and stage one plus kit) however it does not fit properly do to having four headlights it's about an inch to wide to sit between the lights. When I find a reasonable solution I'll post it.


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## CasuallyWreckless (Aug 27, 2007)

mkdeucevr6 said:


> I'm almost done with my vr6 83 jetta and did buy the eurowise radiator (and stage one plus kit) however it does not fit properly do to having four headlights it's about an inch to wide to sit between the lights. When I find a reasonable solution I'll post it.


There's quite a few guys running stock 16v rads as well without issues. :thumbup:


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## mkdeucevr6 (Nov 28, 2008)

Thanks I was able to to drill a hole on the driver side and fit the radiator with two ten inch mishimoto slim cooling fans.


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## mkdeucevr6 (Nov 28, 2008)

I started wiring Friday night I still have the plugged in to the fuse box and I'm using the NLS stand alone harness. I have everything plugged in and the two mk1 coil wires connected to the NLS harness as there diagram indicates. When I turn the key the starter cranks and I have spark but no fuel. I gave the pump direct 12v with a power probe and it comes on so I know it's good and the fuel pump relay tested good with the volt meter. For some reason section N on my fuse box is grounding out instead of giving power to the fuel pump relay if I give it 12v the pump comes on but if I move the jumper wire to another key hot power I get nothing from the pump :banghead: I have an 83 jetta and yes it ran fine before the swap


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## jetta trek (Nov 11, 2007)

mkdeucevr6 said:


> I started wiring Friday night I still have the plugged in to the fuse box and I'm using the NLS stand alone harness. I have everything plugged in and the two mk1 coil wires connected to the NLS harness as there diagram indicates. When I turn the key the starter cranks and I have spark but no fuel. I gave the pump direct 12v with a power probe and it comes on so I know it's good and the fuel pump relay tested good with the volt meter. For some reason section N on my fuse box is grounding out instead of giving power to the fuel pump relay if I give it 12v the pump comes on but if I move the jumper wire to another key hot power I get nothing from the pump :banghead: I have an 83 jetta and yes it ran fine before the swap


Did you test the relay terminal on the fusebox like this below? It all depends if you test wit the key in the on or off position. 

Jump terminals 30 and 87. If the pumps run, the wiring to and from the pumps is fine.
Jump terminals 15 and 87 and turn the ignition key to "on" (not "start"). If the pumps run, the ignition wiring is good.
Connect terminal 31 to ground and check for continuity. If there is continuity, the ground connections are good.
If all of the above tests are passed, that leaves the ignition coil feed to check (consult your repair manual for instructions).

Stupid question, did you check the fuses?


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## mkdeucevr6 (Nov 28, 2008)

Yes all the fuses are new and test good this evening I'll try jumping terminals. I know the pump wiring is good when I jump the red/black wire on the back of the relay to 12v the pump comes on


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## **mk1nutt** (May 11, 2013)

Good info thus far. Ive got a mk4 complete donor wish I could just use everything on it. But I cant find much as far as wiring goes. And woudlnt i need to get a mk3 intake manifold if i use my existing mk4 motor? As well as get rid of the o2j, as eurowise doesnt make a tranny mount for it to fit in the mk1. And i dont quite have the skill to make that mount.


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## jetta trek (Nov 11, 2007)

New wiring info added.


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## mkdeucevr6 (Nov 28, 2008)

So I used my volt meter and tested terminal 30 and I have nothing key hot. I moved the red black jumper to a different key hot post on the box and everything seems to be working fine I've driven it several times now. I'll be wiring up the obd2 scan port this weekend along with trying to figure out why the bolt in my shift weight is now chewing up my clutch cable


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## jetta trek (Nov 11, 2007)

New Resource links added :thumbup:


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## P Slots (Aug 26, 2013)

There are some other companies that make engine mounts for the VR6 for anyone interested in some other options!

Fabless Manufacturing makes a nice MK1 VR6 Engine Swap Kit. Check it out 

https://fablessmanufacturing.com/shop/mk1-vr6-2-8l-engine-swap-kit/


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## 2doorV6 (Jan 29, 2003)

*Great thread for vr6 mk1*

good one to keep an eye on


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## davkime1 (Jun 12, 2015)

*ISO donor car for a VR6 swap on my '92 MK1 Cabriolet*

Hi there. Nice write up. I plan on using a Eurowise kit of some sort. I see they've been adding more items like engine wiring harness, etc the past couple of years. I need to locate a good donor car if possible. I'd alos love to add disc brakes on the back as well. Not a high budget but would like to start rounding up some sources and parts.


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## Alejandro "5t1cky" Segura (Dec 14, 2019)

*Good thread*

I like this thread. It's very thorough. I'm needing some answers though. I have a 1988 VW Cabriolet. I'm wanting to know what's the best most powerful/compatible motor I can put in it and how, if even possible, can i convert it to all wheel drive. I'm wanting to lift it and put some mud grips on it and basically have a little dune/rally car. I know I'd have to buy an engine swap kit, etc. but I'd also like to install a turbo, intercooler, cold air intake, upgrade the exhaust system and get a bigger throttle body along the way. I guess what's the highest MK that I can put in my Cabriolet along with engine specs and governor removal. And if I could just get Specs from there on downwards that would be great. I'm also thinking about gutting out the back seats and just making it a rear mounted motor with a locked rear axle so my tires aren't turning each and every way and finding a steering device from a rwd VW to put in my Cabriolet. If that sentence makes any sense. I know what I want to do, I just need to find an easier way to get compatible part information, input, and build help. Thanks


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## Greme (Dec 29, 1999)

I am getting the urge to do another mk1 vr6 swap. i miss my VR6 MK1 jetta, it was soo much damn fun to drive. the thing screamed. hit 100 no problem. 
i guess i am not surprised at all the swap kits available now, but completely floored at the prices !! 
granted it was 12 years ago but i did my whole swap for around $2,000, including buying the cars 
there was only a handful of swap threads, the best one i followed was by Patron or something like Patatron. 
hopefully the pics are still up, but if anyone wants an old school do it yourself thread, check it out. 








MK! Jetta vr6 Build


MK! Jetta vr6 Build, The Jettatron well, here it is, thanks to, user golf_stream, a perfect jetta shell. this is whats going in for the power plant and this is what i want for the final outcome one of these a day... keeps the hondas away this is my first motor swap, pretty ambitious, i...




www.vwvortex.com


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## emireyes1 (Nov 21, 2021)

hey im 16 years old trying to put in a 2.8 on a 85 cabriolet was just wondering what wiring harness do i need and if yall knew where could i get it?


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