Anyone rebuilt their engine? 1.8l 16v

Assuming its just a broken crankshaft (doubtful). You need a crankshaft irregardless. Replace the rod where the crank broke at minimum.

You have to clean all the parts. Get some gunk for it. Get a ---complete--- gasket set for the engine. Else, buy the gaskets separately as needed to create same. All bearing need replacement. All piston rings need replacement. The engine piston bores need a hone cleanup minimum. Might as well replace the oil pump while you're in there.

Won't know about the valves or seats until the head is pulled. Valves will have to be turned at a minimum. Can be done manually with special tool for that. If too worn, the valves will have to be turned on a machine to create the correct angle again and the seats may be have to be machined as well. Keepers and seals are always replaced. Valve springs need testing for proper pressure at compression of spring.

Camshaft may need replacement, depending on wear. If so replace the tappets as well. Replace timing belt.

Motor mounts are always replaced on a broke engine. Replace all belts. Replace all vacuum hoses. Get the radiator pressure checked and cleaned. Need oil and antifreeze, some break-in lube. Maybe some PermaTex for temp hold on some gaskets. Replace all fuel filters including the one in the rear of the car. Drain and clean the gas tank, allow to dry for few days with all orifices open to the air, give it a few gallons of gas after reassembly and installation.

Get the engine block head mating surface checked for squareness and evenness across the mating surface. Have the machine shop look at the bottom end, may be warped since the crank broke. Block could have invisible cracking due to this as well. Be prepared to invest more money as the engine and parts are investigated by you and the machine shop...

First determine WHY the crankshaft broke! You don't want to spend good money and time and have it happen again while you are on the road! I have not seen them break for no reason! 8^o

You will need to have many items professionally checked and/or machined. Con Rods Cylinder Head Block

You will automatically go with new things such as bearings, seals, gaskets, oil pump, etc.

Usually the Pass side engine mount is good to change esp. when the engine is out, but if you want to change all 3 engine/trans mounts..We won't be mad at you! ;-)

You will probably spend more on rebuilding this engine than purchasing a used 2.0 16V engine out of a later A2 or Passat. Have fun because it does feel good when you successfully do it yourself. ;-)

broken crankshaft ??? what do you mean... is it in several pieces?