My '93 240 will start but only stays running for a few seconds to nearly a minute and then dies, and it dies immediately if I step on the gas, even very lightly. I'm wondering if you can recommend any tests I can do to isolate the problem. The fuel pressure regulator was replaced about a year and a half ago (and the car ran fine for a year and half after that). Also, there appears to be a very small gas drip at the back of the car.

Thanks very much!

 

I'd look at the fuel pressure first, check the MAFS second. Actually, fix the fuel leak in the 'back' first.