Not starting possible fuel pump issue

1999 CHEVROLET EXPRESS
150,000 MILES • V8 • 2WD
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car was not starting did pressure test on fuel line read low so assumed it was fuel pump. when started to drop tank felt empty. if tank is empty would that cause a low pressure reading? just asking before completely remove tank or should i buy 10 gals of gas first and try?
Nov 20, 2021 at 5:31 PM
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SQM
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Hello,

If you are out of fuel, then the pump will not produce enough fuel to have adequate pressure. So, if it is empty then it will be a good idea to add some fuel.

This vehicle should have 60-66 PSI of pressure with the key on and engine off.

What was the pressure reading?


Also, you could have low pressure if there is a clog in the line. Or a dirty fuel filter.
Another possibility is a bad fuel pressure regulator.
You probably want to check those items before dropping the tank for a fuel pump change.

https://www.2carpros.com/articles/how-to-change-a-fuel-filter
https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Please let me know of any questions.
Thank you.
Nov 20, 2021 at 8:35 PM
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the fuel pressure was 10 but don't know if have gas in tank as i started to loosen tank it felt very light. could no gas cause low reading? thank you
Nov 20, 2021 at 9:58 PM
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If there is no gas, then yes it can read low/no pressure. But it will have to be completely empty.
When you turn the key to the on position, can you hear the pump come on?
Nov 20, 2021 at 10:00 PM
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yes can here pump when turn key.
Nov 20, 2021 at 10:02 PM
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Got it. While there is a chance you have a weak fuel pump, it can also be due to a clogged filter or a bad regulator.
Let me know what happens after you add some gas.
Nov 20, 2021 at 10:16 PM
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will do. checked fuel filter when took it off poured some gas through it and it seemed fine and what came out was clean. will add some gas and check regulator. thank you
Nov 20, 2021 at 10:23 PM
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Sounds good.
Nov 21, 2021 at 10:18 PM