Stop! Engine press. low

This 2005 Passat TDI Wagon has had transmission problems, so thought it might be that, since yesterday when I tried backing up, it responded as if in neutral. Then I drove 180 highway miles with no issue. This morning, as soon as I left my driveway, the check engine came on with this message and while in drive I hear a clicking sound, but not while in park. Wondering if it could be damaged crankshaft after I accidentally went over curb earlier in week, or would I have expected the error message to show up before my 3 hour drive yesterday. I probably need to sell for parts, as it sounds like issue will be more to repair than car is worth with 190,000 miles on it.

A few questions to help you along.
What is the oil level on the dipstick?
Has there been a balance shaft upgrade?
What is the rest of the story on transmission history, including when a fluid level check was done.
Any visual damage to oil pan from a curb encounter?

Low oil pressure will make lifters click. I think a balance shaft chain issue is common for stop low oil pressure. Unless you cracked your oil pan on a obstacle.

Check the oil level, and look under the car if the oil pan is cracked.