View Full Version : DIY: B6 A4 1.8T - Taking out a Borg-Warner Turbo

06-21-2005, 02:36 PM
You will need the following tools:
long flathead screwdriver
phillips head screwdriver
straight or preferred is "S" shape wrench for exhaust mani bolts
ratchet set: w/ long & short extensions, a swivel head to make it easy, sockets with metric allen heads on the ends. 1/4" and 3/8" ratchets
I even had shorty 3/8" & 1/4" ratchets with me
Make sure you have sockets with long shafts, as some nut and bolt combos are too long for regular depth sockets.
Star/torque bits set
Allen head wrenches

First start by getting you car in the air, as you will need to get below the car.....ramps work the best, but a jack with jackstands will work as well. Once you get the car in the air and the belly pan off, look at what you're dealing with....look at how all the connections tie into each other. Take digital pics if you can and while you take out the turbo.....this really helps if you take a pic on each thing you do....sequence is the biggest problem people have when they re-install, cause you might tighten something down before you should, etc.

Drain your oil and coolant. The oil drain plug is on the bottom of the oil pan. Bust it loose with a ratchet and socket. Get an oil pan ready underneith. It comes out with force so make sure the pan is far enough away. To drain the coolant at the radiator look at my other thread on refilling your coolant in the DIY forum on www.audigeeks.com
Use the proper size torque bit or phillips screw driver to remove the air tube passage to the airbox (2 screws next to/above the headlight).
Next you need to take the headlight out. Do this with your torque/star bits. You will need an extension to get to the back bolt on the left. Next you need to take out the airbox. This is really the only way for you to get enough room to work.....Next, pop the plastic button off that holds the airbox to the fender wall (it's a 2 piece pop-out screw). Look at all the connections to the airbox, remember how it all looks, then take off all the electrical plugs and hoses that are connected to the box.....you might need a phillips head screw driver for this. If you have one-time clamps on the hoses, most the time you can yank them off. If they're on really well you need to break that clamp loose. I can do it with a flat head screw driver. Just get it between the metal band and try to pry it. It should break off. Have some zip ties or really small C-clamps available for when you re-install it if you broke one-time clamps loose. When everthing is free the whole airbox & heatshield should pull out as 1 unit. Make sure you pop off the solid black smog hose, it doesn't really matter if you accidentally break that clamp on that hose, it's just for the smog pump. But you can usually pop it off clean by getting ahold of both sides really well when you try to pull it off.

With the airbox out of the way, start looking at how the turbo is configured....take a pic of how the lines are attached to the turbo....also a pic on how all the lines are attached to the inlet hose that came off your airbox going into the turbo inlet. Next, take off the inlet hose with a phillips or small socket and ratchet, then the hoses from the N75 that go to the turbo. You will probably be breaking those shitty audi clamps off, the best way is to get some small needle nose pliers or a flat head screw driver. Sometimes you can pull hard enough without doing any damage to pull them off....... I'd recommend getting some C-clamps from the store for re-install here as well....a lot easier than using 1-use clamps. Disconnect all remaining tubes from your inlet hose that are still holding it in place, ie....crankcase breather hose, etc. and pull the inlet hose, the N75, and the DV totally out....you might be able to leave the DV sitting in there. Make a good note on how everything was hooked up in this area. Make sure you also see which side of the N75 valve goes into your inlet hose, for when you re-install. (ie....long end into inlet hose, end opposite to wastegate, perpendicular end to those 2 goes to the compressor side of turbo)

Next get underneith the car and unscrew the clamps that go from you IC piping to your turbo, take it out. While under there, take out the oil return line & Turbo to engine mounting braket. This will work best with allen head sockets, and a swivel head ratchet. The engine to turbo braket might be really tight so just torque them hard....a little oil might come out of the oil return line, but not much so don't worry. While you're down there you should disconnect the black rubber coolant line that goes from your turbo to the engine block....disconnect it at the engine block, it's much easier....you might need to view it from the top to locate it. Remember which thread it goes into cause you might get tricked during re-install. Before you take the coolant return off at the block, put a big oil/coolant pan under the car to let the fluids fall into it, there will be a lot, so just chill for a bit and let it all drain out.....it will get over a lot of engine parts, so rise that area with tap water afterwards. Make sure when it drains it's not getting into you IC pipe/tubes and such. Next take off the oil feed and coolant lines on the top of the turbo(2 stainless braided lines) with a wrench.

Take off the aluminum heat shield that is above the turbo and exhaust mani, this will give you some room to work. They're the small bolts, gold color I think. Use a 1/4" ratchet (extension with some) and appropriate socket.
Now you can loosen the bolts from the turbo to your exhaust mani, and the bolts from your turbo to the cat. Note: to get to the bolt on the far side on top of the exhaust mani, you will need a basic straight or "S" wrench to get that one. After all the bolts to your exhaust mani are out and all the nuts from your cat to turbo are out, you should be able to jiggle the turbo out of its position and pull it out. Don't force it out. Work it out. Make sure everything that's still connected to the engine is not connected to the turbo. With the turbo out you are ready to grab you new K03/K04 and start getting everything back in.

You will need to get the coolant return line installed on the new turbo before install. There's a nasty little gold bolt holding the coolant line on the turbo that will get you if you don't install it on the new turbo prior to re-installation. Make sure you got the new studs nice and tight on the new turbo as well. I used vise grips and a towel to get them screwed in tightly without messing up the threads. I think craftsman has a special tool you can buy to do this as well. Make sure you re-install all connections with new gaskets and crush washers. Don't forget crush washers go on both ends on both sides of the coolant return line. Another hint is to not tighten down all the mani-turbo-cat/tp bolts fully so you can thread everything easier. Then you can tighten everything good and tight. I'd start with the back mani to turbo bolt first. Just install everything in the reverse order of install, it should be more clear what you're doing by this point. Make sure you top the coolant reserviour. You will need to drive around a bit and top off the coolant again.....and maybe 1 more time after that. I also put a little engine oil in the oil feed side of the turbo with a straw before I re-connected the lines so the turbo has oil on startup. It will smoke on startup for a minute or so. That's usually just the crap and oil from your hands on the turbo itself burning away from the heat. No big deal. Make sure all your connections are good and TIGHT and all the hoses and connection are actually on. Make sure you refill your oil. I'd also recommend getting a new oil filter while you're at it.

That should be it, I don't think I forgot anything. It's nice to have a bently manual (cd) around in case you need to see diagrams of the engine bay and such. Make sure before you re-install that you have a hardware kit from a tuner.....buying all the necessary hardware from audi is too expensive.....try either:

Should be around $40 for a hardware kit.
I've worked with both these companies, both owners are great guys.

Good luck, and I hope everything works out for ya. If you have any other questions, or need pics of some of my steps during the process feel free to PM me.

Have fun with it, think of it as a big legos project. This could probably be written up better, but whatcha gonna do.