May 22 2008

Front end.

The front end if course has far more components to remove and more complex. But, following the manual and applying common sense, it is pretty straight forward task. The points to remember:

- I can make job easier by cutting off tubing which got stuck under pressure of clamps. That applies to engine coolant, fuel supply and other lines I'll have no need for. Preserving those would be difficult.
- I mark all the connectors I'm unplugging. Later on this will help once use OBD scan tool to see what the car complains about missing. Simulation normal sensor outputs is easy. Find which is which, is not that easy unless you've done 10-20 Audis already. I didn't.
- If you unbolt parts, insert bolts back into threaded holes rather than throw in the bucket. Very soon bucket will be full and you won't remember which bolt goes where if the thread is the same but the length is, say, 10mm different. Either one will fit, but each bolt has its purpose. Better to stick to original assembly. There will be enough chances to improvise.

Starting from front bumper and whole carrier holding head lights and radiators. This Audi has no metal body around front, and once front is unbolted, engine is totally exposed and convenient to deal with.

Outside air temp sensor and PS fluid cooling loop in front of the A/C condenser radiator.
Removing plastic guards on both sides
Audi uses clever plastic latches, locks and fasteners wherever possible. These hold condenser in place
The liner under fenders is removed. This exposes engine compartment, there is no sheet metal separating it from outside.
Engine compartment view without liner.
Unbolting front bumper.
The bumper is off.
Draining antifreeze.
Wire harnesses will get disconnected everywhere. This is one such cluster near ABS unit.
Disconnecting brake fluid hoses
The front carrier is out. On this photo it is on the floor in front of the gas tank standing upright.
This is what the marvel of German engineering look like.
View from the other side. You can't see the mess on the floor, but believe me, EV will never have this problem of leaking liquids!


Next let's get prepared to unhook everything from the engine, so it can be removed. Since it is bolted to the transmission, I'll just remove both together as one unit. Probably it is easier to sell it that way too. Because of front half-shafts are linked to the transaxle via flanges (as rear suspension), not inserted into transmission and retained with C-clips as in cheaper cars, removing engine with transmission is simpler. There is no need to remove ball joints to pull half-shafts from the transaxle. You will see.

Removing wipers is not as easy as you might think. Special puller was used.
Now wipers drive cover is gone so the car brains (ECU - Engine Control Unit) can be accessed.
Plugs in ECU compartment. Large bundle of wires enters passenger compartment from here.
Plugs to various sensors coming from ECU unit. Almost all of them will not be used. However, without ECU the dash will be dead, so ECU will stay. More on fooling it later.
Removing throttle plate.
The belt is out. Time to remove A/C compressor and generator to expose engine mounts.


Now it's time to cut hoses and remove these major components.

Removing oil cooler, which is the way [of access to the A/C compressor].
Compressor is unbolted.
Its electric clutch wire is unplugged and the unit can be removed.
Unbolting generator. IT was always mystery to me why people use term "alternator". Since rectifier is built in, Its output is DC, not AC, isn't it?
Unplugging connection to the starter relay.
There is common harness between starter and generator. So it has to be removed. The starter is a bit deep inside, but accessible.

I label everything I disconnect unless wiring destination it obvious.
Unbolting front half-shaft guards. Several extensions were reused - about 1m long as the bolts are deep inside.
Unlinking front half-shafts from the transaxle. Special Torx bit is needed here.
Plain C-clamps will prevent half-shafts from turning while flanges are unbolted.
Half shafts are unlinked from the transaxle.
Engine supports now are loosen up. I'm getting close to lift the monster...

NEXT


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