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Discussion Starter #1
Car is a 2000 SPI with about 90k miles on the fuel pump, about 150k miles on the rest of the fuel system. I've read where it's been said that a failing fuel pump with show increased fuel pressure.

I looked up the specifications on the fuel pump and it says:

pressure should be between 35 - 65 psi.

I've noticed that my pressure was always, as noticed in the last year anyway, around 38 - 43 psi.

Just recently I have twice observed pressure to be between 50 - 55psi. The first time it stayed there for the 20 minute trip and didn't drop back down until the car was restarted. The second time it stayed there until I turned the A/C on and the coolant temp dropped back to 192 F - after a while.

During both times above, the fuel pressure jumped to 50+psi after idling for longer than usual and the coolant temp got to 221 F before the cooling fans kicked on.

Is this normal operation of the fuel management system when engine temps increase - causing an increase in fuel pressure or the sign of an aging pump?
 

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IMO if the pump makes enough noise to hear between turning on the key, and starting the car, it may be in trouble.
Problem with fuel pumps, they pretty much work or do not work. Mialeage doesn't matter. More important is: has the tank ever run dry? more running with no fuel, more likely to die.
 

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On earlier models, the "sock" that filtered the fuel B4 it got to the pump tended to clog up, making the pump work harder, leading to early failure.

The only "sign" was either engine "missing" when cornering with a low fuel level, or "missing" (also "lack of power) at speed on the highway - also more prevalent when fuel level was low.

As noted above, if it works - it's fine, since there aren't any warning signs of imminent failure. The "warning signs" above are actually from the clogged filter, NOT from a pump issue...
 

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Discussion Starter #4
Tank has never run dry and I actually cut an access hole in the floor and replaced the 'sock' about two months ago.

The Chiltons shop manual actually calls out to listen for the pump to come on for about two seconds when the key is turned to the 'ON' position - which it does so all must be fine.

Maybe it's always been this way but I just noticed it when sitting in the car on a hot day idling while waiting for someone....
 

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Hey. it happens - when you are worried about something, any possible symptoms tend to worry you - noises that weren't noticed B4, test results that you aren't sure are "normal'....

I had to replace the sender unit, "sock" included in my Pick-Up Truck - it's got 140,000 on it now & the original pump is still working....

Didn't have the $80 to spare to put a new one in as a "preventative", and you never know, even a new one might fail B4 the old one.....
 
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