Cadillac Repair: hard time starting my 99 cadillac deville, fuel pump relay, cadillac deville

Question
about 3 months ago i bought my first caddy. it was off of my dads girlfriend in vary good working order. It had about 80,000 miles on it.  About a month after that i ran it out of gas and ruined the fuel pump. Ive had 2 new fuel pumps put in since then and still it takes 3 attemps  normally to get it to start. Once it starts the fuel pressure is normal, but once you turn the key off it instantly drops. Any idea what could be causeing this? and also when im not applying the gas my car makes a hig pitch noise/ hum , i cant seem to figure it out, if you could help me please send me some answers thanks

Answer
Fuel pump test:

1. Get yourself a helper.

2. remove the gas cap.

3. have one person listen in the gas tank at the gas cap opening.

4. have the other person turn the ignition switch to the ON position ONLY so as the dash lights come on. Do NOT attempt to start the engine.

5. As soon as the ignition key is turned to the ON position, The person at the gas tank should hear the fuel pump run for TWO SECONDS and then it should STOP.

6. Does it ?.


If you do NOT hear it run, in most cases the fault is the fuel pump relay or the fuel pump..



let me know.


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