1990 Other Volkswagen Models VW Corrado

I would suggest searching for any vacuum leaks. Check all of the vacuum hoses for any cracks or loose connections.

If you can get the engine to run at least idleing low, you can spray carb. Cleaner on the vacuum hoses and if the engine revs up when you spray a certain hose, that one is leaking.

Most likely not. Sorry, I had mis-noted that you said it completely died now.

You may need to replace your EGR (exhaust gas recirculation) valve. There are two types, the electric and the vacuum type. Since your vehicle was made pre-1994, I am thinking that your vehicle has the vacuum type EGR valve. It should be held on with a couple of screws somewhere near your intake manifold. It is all related to the vacuum effect though, which I still believe is the cause of your vehicle troubles.

Please post your results and I will follow up.

The fuel injector may be past repair, but the first thing to do before paying out high dollars for a mechanic is to run some fuel injector cleaner through the system. If the injector is clogged, this should clean it out. If it doesn't (or if you can't get it started to do so), you can remove the injector yourself and clean it out with a very tiny tool of some sort to ensure it is not clogged.

I'm just curious. When was the last time you changed the oil? If the oil has broken down then there is nothing to keep the fuel/air from blowing past the rings into the crankcase. With your mileage, I would consider putting some ring restorer in it and change the oil.

Those are the only two ways, that I know of, that would cause fuel to get into the oil except manually putting it there.