Fuel Problem When Hot

[GR82BINSPIRED]

I recently put a new fuel pump in my 2000 Blazer. It runs great and I am getting the best gas milage since I bought the car in July. My problem is after the car has been running for awhile and i turn it off it will not restart right away. If I let it sit for a few hours it fires right back up. I took it back into the shop and they tested fuel pressure after it would not start and it was low 40psi. then it went down to 0 So now shop wants to put another fuel pump in. Do you think i got a bad pump or is there another problem. if by chance the car starts while it is hot it will stall out and carb cleaner wont start it up. The only way it starts up is after it cools down. If it is a bad pump im thinking of telling them to put in an OEM pump which costs close to $600

[Chris Stewart]

Check your ignition spark with a good spark plug after you do a hot shutdown(won't restart) to be sure the ignition coil isn't breaking down with heat.
Did you see the low fuel pressure on the gauge?
Harbor Freight has a reasonbly priced fuel pressure tester.

[GR82BINSPIRED]

yes i saw the low fuel pressure on the guage. we put another fuel pump in and it seems to be starting ok right now. but we will see. the fuel pressure is at 65psi now

[old_master]

Cold fuel pressure must be 60 to 66psi, engine off, pump running. After the pumps shuts off, fuel pressure must remain above 55psi for 3 to 5 minutes. A drop in pressure below 55psi indicates excessive leakdown. Diagnosing an internal leak requires shutting off the fuel pressure line between the pump and the pressure test port, after the pump has built pressure.