Pump Signs

what are some signs of a fuel pump going?

i have a 2000 pontiac grandam w/ 120000 miles on it
the car will shut off like its out of gas after driving for a little while. it always happens while im driving(going 55mph or something), not when i stop or slow down, and if i let it sit for 5-10min without trying to start it, itll turn over and run fine, then i just try to get home or somewhere for the night and let it cool down

Thats a hard one, but the straight forward answer to this question is that Jerky styles, periodic hard hot starting and sudden engine stopping and not re-starting are great signs.

Low performance may be seldom because the onboard computer could enrich the mixture when low pressure exist up to certain predefined threshold.

Goodluck.

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