fuel pump fuse location 93 century

check on the fire wall or it might just be a relay turned on by the computer

Look behind the RH headlight to the right of the radiator. There's four relays mounted linearly to to a metal support. The one closest to the engine is the fuel pump relay. The fuel pump fuse is mounted in it's own dedicated fuse holder closest to the fuel pump relay.

Garrett Fulton

Look under the hood behind the r.h. headlight. There are four relays in a row, left to right, attached to a support to the right of the radiator. The fuel pump relay is the one closest to the engine. The fuel pump fuse is in it's own dedicated holder closest to the fuel pump relay and also attached to the support.

Garrett Fulton

Thanks. The problem I am having is that the fuel pump quits and the car won't run, and a few hours later everything is ok. Any idea where the problem may be?

"Milton Green" wrote in message news:rzj6e.12139$ snipped-for-privacy@twister.nyc.rr.com...

The pump receives current through a parallel circuit. One side is a set of contacts in the oil pressure switch, the other side is the pump relay. When the key is placed to run, the pump relay is closed by the ECM for two seconds to pressurize the fuel rail. The pump is turned on again by the ECM during crank. Once the ECM senses the engine is running, it deenergizes the pump relay. But since there is now oil pressure available, the fuel pump contacts of the oil press. sw. are now closed and the pump continues to run. I reckon they design it this way to prevent the pump running after a wreck and adding pushing fuel out of a broken line. I had a problem similar to yours on my '93 3/4 ton Chevy diesel pickup which has a similar pump control circuit. The contacts of the oil pressure switch had developed high resistance and the pump was only getting 7 volts. But since your Buick has to sit for awhile before it will restart, I'm thinking that the windings in the fuel pump are opening up after the pump runs awhile and warms up. After it sits and cools down, the circuit remakes and the pump will run again until it heats up. My boy's '93 Century has a pump that will only develop 25 psi when it should be supplying 41-47 psi and will barely run. I've got to drop the tank and change the pump out tomorrow. I've got an Alldata subscription for the car and since it's the same as yours, if you want I'll email you a graphic of the pump electrical schematic. If you check that schematic and wait till the car dies on you, you could put a meter on the output wire going from the pump relay to the pump right after it died. (Pull the relay out of the socket first). If it shows an open circuit, them I'm likely right about the pump windings opening up. I'd like to know how you come out on yours.

Garrett Fulton

I had the pump replaced, so unfortunately I won't be able to test your theory. Thank you very much for your input. It has been an education.