3.0L to 1.8T swap?

[B5REALLY]

I have a 2002 A4 Quattro with 3.0L and 6 speed MT. The V6 blew and I'm noticing that AVK engines are few and far between and more expensive compared to the 1.8T engine. I just use my car as a daily and don't need to go fast. Other than the wiring harness and ecu, what would be involved to swap a 1.8T into my car?

Will it mate up to the 6 speed MT?

Is the core support and radiator the same?

Will all the electronics work in the instrument cluster properly with the different ecu and wiring harness?

I have limited money to get this car back on the road and I'm looking for the cheaper way out because I still owe money on this car. I have all the tools necessary to do this kind of work and will do the work myself.

Any advice would be much appreciated

[itsmatt33]

here u go http://www.audizine.com/forum/showth...T-build-thread

[nein-reis]

Oh hai.

Its a easy swap if you have a manual.

Part 1. Hardware:
Full 1.8T engine, including all accessories, brackets, mounts, lines, and electrical.
*You will need a full 1.8T wiring harness and ECU*
The passenger side 3.0 A/C line will work, the smaller drivers side line will need to be a 1.8T line.
You will need all 1.8T coolant lines and hoses along with a 1.8T radiator. I found a new OEM radiator for 120.00
If you do not have 1.8T knock sensors you can use the 3.0 ones, they are the same except have longer wires to harness.
Existing power steering lines will work however you will need to have one 1/2 foot adapter line made, I had mine made at Evco for 9.80
Subframe is the same but you will need new motor mounts, this is a good time to upgrade them. I bought a full Stern set including trans, motor, and snub.
Fuel lines will need to be modified. I used a B5 fuel rail to connect to the existing return system. The fittings on the 3.0 fuel rail are direct fit to the B5 rail, just extend the lines over the firewall with proper hosing. Fuel lines need to be converted from 5/16th hard line to -6an. You can use either pushlock hose (cheaper) or stainless braided line or whatever after that. I used two of these: http://www.jegs.com/i/Earls/361/1651...rentProductId=
The 3.0 is a return system fuel using a on-rail fuel pressure regulator while the B6 1.8T is a static returnless system using a in tank pressure regulator. Use a B5 1.8T fuel rail and FPR and leave the FPR unconnected to make it work. The snub mount will need to be modified if you are re-using the 3.0 front clip. You have to shave about 1.5" off the left side.
Assuming you have everything else needed (manifolds, hard lines, coolant lines, oil housing, sensors, etc...) it will all go right in with no modifications.
Power steering line has a compression fitting then a hardline flared female fitting that fits to the 3.0 power steering pump. You need to lengthen that line out... I took it to a local hose shop and they made me an extra foot lengthen it for the new pump. was under 10.00 to do so. you need ALL 1.8T accessories and brackets from that model year.

Part 2. transmission:
If you are using the 3.0 6 speed manual transmission you will need to take the 3.0 converter plate off the front and replace it with one from a RS4 part number: 01x103551 (runs about 280.00)
Also, you will need to replace the 3.0 starter with a 1.8T starter. I bought mine from Ray at RAI for a very fair price. You will need to order new starter bolts also.
After this it will bolt right up to the 1.8T block. I also recommend buying the 1.8T trans shield for around 38.00 from the dealer, it will keep anything from entering the bell housing since it is now open around the smaller block.

Part 3. ECU and electrical
You need to "chip" flash the car with a immo deleted software and use a 1.8T B6 ecu of the same year as your car. your gauge cluster will work fine. However the 3.0 gets it speedo info from the ABS module, and the 1.8T gets it from a sensor in the trans...your 3.0 trans does not have a sensor. Your speedo will continue to get info and work fine from the ABS system, but you will get a check engine light for the sensor not in the trans. You can buy the sensor and plug it in and it will fix the issue, thats the only cluster issue I had.
Also, I used Maestro to code out my system and tune it all in, if your not going BT or dont want Maestro I dont know what issues you will run into there.

Over all it is a very straight forward swap, and not much extra hardware is needed. After the completed engine you only really need a starter, radiator, RS4 trans spacer, B5 fuel rail, ECU, and a bunch of line and hosing. The swap really only took a few days of 4 hours a day work. But I did not have it running for a few months. After I had it all together the crank was frozen because the flywheel was hitting the bell housing and stuck. So we spent months trying to find a fix before finding the RS4 transmission spacer... luckily we know that now and you will not have that issue.

[Styleprojekt]

You could buy my 3.0 motor too

[The1nutwonder]

on that idea. cause ur prob gonna spend a fair chunk of change getting all the needed parts to swap when can just buy a 3.0 and b done with the headache.

[sandspeed]

on that idea. cause ur prob gonna spend a fair chunk of change getting all the needed parts to swap when can just buy a 3.0 and b done with the headache.

Yeah, that would be a waste of money, especially since he wants to go from a 3.0 TO a 1.8T. :facepalm

[road_tripper]

Yeah, that would be a waste of money, especially since he wants to go from a 3.0 TO a 1.8T. :facepalm

I think he meant that that since the OP is asking about the cost of swapping to a 1.8T since AVK engines are scarce and expensive... that in the end an expensive 3.0 replacement engine will be cheaper and less headaches than 1.8T conversion?

The OP sounds like he wants a running car as cheap as possible... not looking for a 1.8T for modding or anything else.

[B5REALLY]

I wonder how much doing this swap would affect the trade in value of the vehicle even if done properly

[sandspeed]

Your car will have no trade-in value, done properly or not. You would be hard pressed to find a dealership that will take a car that has a different size engine than the one it rolled out of the factory with. An enthusiast might buy it, maybe...

[Torchwork]

I'll buy your ecu

[BCsniper]

I know of an A6 3.0 that just got its engine replaced (with a ~60k mile used one) you could buy the whole car from this guy for $3-3.5k and part-out the A6 and keep the engine.

[Elliott]

Your car will have no trade-in value, done properly or not. You would be hard pressed to find a dealership that will take a car that has a different size engine than the one it rolled out of the factory with. An enthusiast might buy it, maybe...

Yep. It's sad how little our cars are worth these days.

[imnuts]

You're going to end up paying more to buy a 1.8T and put it in the 3.0 than just buying a new 3.0 motor.

[movement360]

dude, swap in a vr6