fuel pump relay problems?

1999 BUICK LESABRE
86 MILES
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HMAC300
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thepcm turns thepump on why would you wantto bypass this circuit? if it'snot working then find the short or poor connection between relay and pcm and fix it.
Aug 4, 2020 at 12:56 PM (Merged)
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BEVIS79
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I have a 91 Buick LeSabre Custom that will rotate but not start also, it makes a click noise by the ECM. It has 3/4 tank of gas. This morning it started and 3 hours later it did not. I replaced the fuel pump relay today. I had the fuel pump put in 1and 1/2 year ago and have not let my gas go under 1/4 tank since. please help me.
Aug 4, 2020 at 12:56 PM (Merged)
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JDL
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Sorry for the late reply.

If it cranks good but won't start, have a helper crank it while you visually check for spark at the spark plugs. If spark everywhere, check proper fuel pressure and fuel injector pulse.

As far as the noise your hearing, might be a relay or even an hvac actuator that has a problem?
Aug 4, 2020 at 12:56 PM (Merged)
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REDNILLA
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V6 front wheel drive automatic 199,000 miles.

Engine cranks does not start, no sound of fuel pump hum at key on and car has been sitting for a year. Where is fuel pump fuse and relay located? If fuel pump fuse and relay test good can fuel pump be removed without dropping tank? How?
Aug 4, 2020 at 12:57 PM (Merged)
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2CARPRO JACK
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Fuel pump relay is behind right side of dash in fuse/relay center. Check fuse number six in the same center. The tank unit cant be done with the tank in the car, sorry, needs to come out.
Aug 4, 2020 at 12:57 PM (Merged)
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REDNILLA
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Thanks for the information and I assume you are referring to the fuse/relay bank under the hood on right side? If yes, great and you stated to check fuse number six, and it is good. which relay? anyway to test the relay?

Appreciate the response!
Aug 4, 2020 at 12:57 PM (Merged)
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2CARPRO JACK
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According to my software there is a fuse/relay panel under the dash on right hand side. Might need to remove the plastic panel to gain access.
Aug 4, 2020 at 12:57 PM (Merged)
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KASEKENNY
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I attached the location of the fuel pump relay with a diagram for future reference. Please let us know if there are more questions. Thanks
Aug 4, 2020 at 1:36 PM
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