This is a 1990 Chevy Lumina 3.1 EFI 127K miles. The problem I am having is this car sat for close to two years. It was tuned up just prior to being taken out of commission. I was able to get it started and let it idle for approx 20 mins before driving it. I was able to go about 1 to to miles before it stalled. The gas in it was old, I had about 1/2 tank and added another 1/2 tank and some fuel additive. I am still having a random stalling problem. It will start in the morning and run fine for a while then I notice the oil pressure drop to next to nothing and the engine will quit. I know nothing about car engines, but I am wondering if it is just a gas problem and that once I get this tank of gas run thru that it will be ok or if I will need to take it in to get someone to look at it.
I have driven it for 10 or 15 miles with out it stalling then it will just quit. I have no clue. Help