Fuel Pump Runs But Sometimes Makes No Pressure

[old_master]

You have experienced a VERY common problem that the Airtex pumps have. There is a check valve built into the pump output that doesn't operate correctly, poor design I suppose. The valve retains pressure in the line after the engine is shut off, to reduce prime up time on the next start. (You are correct, the pump is supposed to run briefly after the key is shut off for the same reason.) I have seen this happen on countless Airtex pumps. Don't be surprised if it happens again, like I said, VERY common problem. I recall one vehicle in the shop, we went through 3 Airtex pumps in a row...all bad, same problem. Vehicle never left the shop until we installed a Delco pump. Needless to say, we don't use Airtex pumps any more. The first sentence in your first post was a dead give away to me.

FYI, in the future... Blocking the return line can do permanent damage to the fuel pressure regulator if pressure is allowed to rise above 75psi.

Glad you figured it out and got her going.