96 astro no power; won't start

Does anyone have any idea what my 96 astro is doing now? We replaced the power steering pump on Monday because I was stuck with no power steering or power brakes. Picked it up from the shop and it worked fine. Drove it the next day and it loses power - doesn't stall, just doesn't want to go with the pedal floored. Then it picks up and is fine. Now it stalls out and doesn't want to start. Please don't tell me it's the fuel pump; just replaced in August on moving day!!!!! Second one in 3 years.

PCV valve maybe?

The first part of of losing power sounds like the TPS (throttle position sensor). It's located right next to the air intake hose connects to the intake manifold.