How dire is the situation? Stop driving immediately and take to the shop? It can wait a few weeks? Needs to be addressed eventually?

 

That makes a lot of sense. I guess we'll see what the mechanic says after he talks to Audi Warranty people. thats really the deciding issue here.

 

By the way, if it turns out you need to replace the head gaskets, I bought mine from Arizona Autohaus for $ 18.60/piece.
The style for your car (I don't know what car you have) may be more expensive but is much cheaper than PartsTrain's $ 60.

 

Thanks for the tip. Mechanic estimated 25-30 hours of labor for the repair. Does this sound about right?

 

So I spoke to Audi Warranty, and they say that the engine overheating (and causing the gasket issue) is "consequential damage", which is not covered.

They said for example, if the alternator were to blow up, and damage the hood, that would be considered consequential damage and the hood would not be covered. This is the most ridiculous thing I have ever heard.

Anyway, here is what we know:

1) Thermostat failed and caused engine to overheat
2) There are hydrocarbons present in the coolant system, which should not happen. But there is a small amount (34ppm). Mechanic says this may lead to overpressurization of the coolant system and cause leaks, cracks, etc. Is this level acceptable or does this need to be fixed asap.
3) There is a syrup-like smell after driving the car

Suggestions for what to do next?

 

Oil leak...


Look around... your leaking somewhere, and it doesnt have to be the heads. There are o-ring seals that could have blown, the coolant reservoir could be leaking, freeze plugs could have unseated, radiator cracked, hose with a pinhole, etc. Shoot the mechanic could have not sealed the thermostat housing correctly or left a bleeder screw loose.

Point is, look around and trace the problem first, then you'll know which direction to take. Could be a cheap fix.

 

I misspoke before, the hydrocarbons were fount in the coolant system. Basically, my understanding is the only way that hydrocarbons can get into the coolant system is if there is a problem with the head gasket.

 

......or the oil cooler, or the oily funnel used to top off the coolant.

Check the coolant level very carefully before and after going for a drive. Steam coming out of the exhaust when the car is warm will also be a red flag. The G12 leaves a nice pinkish white residue behind when it evaporates so external leaks are quite easy to spot.

As far as the labor hours go, I think I could replace a pair of head gaskets in 16 hours, replacing timing belt, pump etc. while I'm at it.

 

Oil in the water will cause mayonaise - a white substance -easy to spot. I once had an Alfa Romeo that would blow the oil seals every 10K or so and the teltale sign was white gooey stuff in the radiator. LOL

 

I had a blown head gasket in my range rover. Chances are good that if you have HCs in your coolant it is a head gasket leak. You can check for fluid on your plugs as the coolant will blast into the cylindar at about 150psi and will pressure wash the cylindar. Be careful on this one. I think that Audi uses aluminum blocks which warp when they overheat. If they warp too much they will not be rebuildable and you will be out an engine. Make sure that they machine the heads down to flat again before rebuilding. This is what I call major surgery. Sometimes it is almost impossible to detect, but the best time to catch it is a rough idle during the first few seconds of startup and obviously the other mayonaise and smoke tips, but they won't be there unless you have a bad leak. Hope all goes well.