Engine/transmission swap
- Thread starter gbpakrz
- Start date
300D
Veteran Member
And the fuel system is a bit different too which will be part of the wiring that NERO is talking about. You will need to bring the ALH's fuel pump with you into the 2004. Bonus is the 2004 has an in-tank pump to help out the ALH's VE pump.
I also imagine the ECU will need some work as well. Either a swap or a rewrite, which don't ask me about as that is way over my pay grade.
Rrusse11
Veteran Member
I hope you're not planning on swapping the auto transmission as well?
gforce1108
Top Post Dawg
- Joined
- Aug 2, 2006
- Location
- Newburgh, NY
- TDI
- 04 Jetta GLS BEW, 14 Audi A7 V6 TDI, 13 Porsche Cayenne V6 TDI
It will bolt up - but it won't run. Very different engine. Take the 5sp out of the 04 and put it in the 02. That will actually work
Alchemist
Veteran Member
It has been done. http://forums.tdiclub.com/showthread.php?t=495567
Here is the story as best as I can remember it. Keep in mind that this information is based on a manual transmission. An automatic will throw a curve at you, and I haven't looked into the possibility of doing that.
Mechanical:
Everything bolts up just the way it should.
Fuel:
You will need the lines from filter to IP.
Electrical:
Replace both engine bay harnesses and ECU. Get the immobilizer disabled.
To use the lift pump, connect the Black/White wire (On ECU connector T121 Pin 120) from the IP shut off solenoid to terminal 85 of a relay. Ground terminals 86 and 30, and connect terminal 87 to the White connector in the plenum T10w Pin 7. This is necessary because the ALH uses +12V to operate the fuel shut off while the BEW uses a switched ground to operate the lift pump relay.
If you don't use the lift pump, just change the in tank pickup. No electrical changes are needed.
I used the entire air intake system, including intercooler, due to the differences in connections on the intercooler and turbo.
Exhaust:
The downpipe will bolt up to the turbo, but if you remove the oxygen sensor, plug the sensor bung. Auto parts stores can supply the plugs.
Plumbing:
Because of the different placement of accessories, both lines to the AC compressor and power steering pump need to be swapped, as well as the coolant line from the metal tube to the reservoir.
This means you will have to refill the steering fluid, and evacuate, then recharge the AC after replacing the drier.
The accordion tube from the air filter to turbo inlet tube needs to be swapped due to length difference.
The vacuum line to the brake booster is also different and needs to be swapped.
Inside car:
No changes needed. Everything works if immobilizer is disabled.
Here is the story as best as I can remember it. Keep in mind that this information is based on a manual transmission. An automatic will throw a curve at you, and I haven't looked into the possibility of doing that.
Mechanical:
Everything bolts up just the way it should.
Fuel:
You will need the lines from filter to IP.
Electrical:
Replace both engine bay harnesses and ECU. Get the immobilizer disabled.
To use the lift pump, connect the Black/White wire (On ECU connector T121 Pin 120) from the IP shut off solenoid to terminal 85 of a relay. Ground terminals 86 and 30, and connect terminal 87 to the White connector in the plenum T10w Pin 7. This is necessary because the ALH uses +12V to operate the fuel shut off while the BEW uses a switched ground to operate the lift pump relay.
If you don't use the lift pump, just change the in tank pickup. No electrical changes are needed.
I used the entire air intake system, including intercooler, due to the differences in connections on the intercooler and turbo.
Exhaust:
The downpipe will bolt up to the turbo, but if you remove the oxygen sensor, plug the sensor bung. Auto parts stores can supply the plugs.
Plumbing:
Because of the different placement of accessories, both lines to the AC compressor and power steering pump need to be swapped, as well as the coolant line from the metal tube to the reservoir.
This means you will have to refill the steering fluid, and evacuate, then recharge the AC after replacing the drier.
The accordion tube from the air filter to turbo inlet tube needs to be swapped due to length difference.
The vacuum line to the brake booster is also different and needs to be swapped.
Inside car:
No changes needed. Everything works if immobilizer is disabled.