Left the car outside the other night.
Started the car next morning (COLD), let it warm up at idle; came out 5 min later: engine overheated, 2 qts of oil under car.
What happened?

I assume the coolant mix I was running was NOT mixed for the extreme cold, and froze overnight.

Where should I start?

Are there 'freeze plugs' on the 1.8T AEB?

Car is not here, left it where it was parked when it happened. Going up there right now.

Any tips, suggestions, where to look, what to check are VERY appreciated!

 

Water pump froze solid, couldn't spin, timing belt burnt up on the water pump pulley and broke, pistons hit the valves and destroyed your engine. Thats worst case but 2 qts of oil under the car is never good news unless you forgot to put the plug back in when changing the oil. Oil won't come out a freeze plug hole unless the oil got into the water jacket somehow, like a blown head gasket, cracket block etc. either way I would not expect good news.

 

Update:
Topped off coolant (not much missing) with hot water.
put 2 quarts oil in (to have some oil).
Started engine.
Oil squirting out between oil cooler and oil cooler housing.
Removed.
O ring looked 'square' and flat, ripped (not sure if ripped on car, or ripped when removed).

Will take oil cooler off spare engine block; new O ring ordered. Not sure if dented from freezing?

Assumption: coolant in oil cooler froze, relieved pressure on O ring. High viscosity, high pressure (bypass valve oil filter?) forced oil out O ring; old O ring not elastic enough to re-seat.

Final verdict later when cooler and O ring installed.

 

Wow, sounds like you may have lucked out, but that oring is suppossed to prevent oil from leaking out between the cooler and the block. I wonder if the cooler split internally and mixed water and oil together and when that froze it pushed the o-ring out, or maybe it crushed the tubes in the cooler and the oil back pressure blew the seal out. Keep an eye on your oil to see if it gets milky. Get some more antifreeze in there.

 

will do. We will drain oil and put fresh oil in. Ditto coolant.

 

I'll try not to be a *****, but don't post misinformation like this. You seem smarter than that. Timing belt does not drive the water pump on 058 blocks. And even if it did, the belt wouldn't "burn up." They have teeth on them. Either the teeth would shear off (which wouldn't happen), or the pump would spin (which would happen).

 

Sorry my 2.8 is driven by the timing belt, and is driven off the smooth side of the belt not the toothed side. And yes if you freeze the water in the block solid, or mostly solid and have a belt driven water pump the belt will heat up going past the frozen pulley and eventually snap. I have seen it happen on non audi's engines. Of course there will be a horrific belt squeal and rubber burning smell coming from the belt drive area.

 

I have replaced that o-ring between the housing and the cooler before. Lucky me I did it during the summer.

Your in Michigan, right?

It must've been like -15 up there. The coldest my baby has seen this year was around -5.