What is the voltage reading I should get at the three wire plug that is above the differential for the fuel pump.?

 

0v when the engine is off, 12.5v with the engine off and a fully charged battery, and 14.5v with the engine running and a working alt. It should run momentarily when you key-on, then stop and wait for cranking or running.

GD

 

Thank you. Ended up the pump was seized. So I had to swap it. Odd thing was the strainer had mostly dissolved some of the strainer was left and its mounting parts. , the rubber seals had turned to a sticky mess. On a 7 year old pump.

 

Sounds like it may have not been Ethanol safe. Or was really poor quality. I generally use the Deatschwerks DW200 (255LPH) pumps - they have a kit for the C4 Vette that fits alright. I usually just buy a new pickup/sending unit assembly (Spectra seems the better of the two out there) and those also come with strainer bags, and hose, and such.

GD