Signs of a bad or going bad fuel sending unit or pump

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454cid

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The hard start symptoms you describe could be the fuel pump, at least in part. Get a gage on it, first.
If you do change the pump, swap to the new 4-sqaure wiring harness from the stock flat-4. A lot of times the pump will come with the pigtail.

The fuel gage is another issue. It's probably the air core motor in the gage cluster.
 

454cid

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Can anyone elaborate on this?

It was a design change by GM, on the connector. Apparently the original design didn't handle the load very well.

The way I wrote that originally kind of makes it sound like you have a choice, on the connector. It really depends on the pump. There are some pumps that still have the original design connector, especially if old stock. I went with a Denso pump, and it came with a new pigtail for the new connector.
 
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Intenseman

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Like has been said about the cheap fuel pumps, sometimes the impeller implodes and ruins the pump. I always replace my pumps with AC Delco. Spend the money and save the time of replacing it in a year or two. Also on the wiring harness, I've had what I thought was a fuel pump failure only to find out that the wiring harness had failed. Plugged in the new wiring harness and I was good to go. I think that pump is still running today.
 

Chris Ingham

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If these in-tank pumps keep failing, has anyone to fit an in-line electric pump instead.

Sent from my B3-A40 using Tapatalk
 

Schurkey

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95 Yukon 4door driver side

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Cutting a hole in the body for fuel pump access is SUCH A TERRIBLE IDEA. For FUKK SAKES do NOT do that. Not unless you're skilled at metal work--welding, fabricating, etc.

The odds are low, but the stakes are very, very high.

Let's say you get T-boned, and that Tahoe rolls onto it's roof in the ditch. IF (big IF) the fuel tank ruptures, all that gasoline is going to be funneled into the passenger compartment, past the access hole you cut.. Maybe you're unconscious. Maybe you've got kids strapped into car-seats who can't get out on their own. Maybe the seat-belts jam. Who knows?

That gasoline catches fire, and everyone inside burns to death. If you're LUCKY, you die of smoke inhalation instead of the actual fire. Anyone conscious and burning to death will be screaming, begging to die soon.

THAT'S why GM does not provide an access panel. Even if you have a panel bolted-down, sealed with a gasket (or tape)--if that section of the body crumples, it'll potentially leak. All that's missing is the fuel-tank rupture. Ford used a single sheet of metal to separate the gasoline in the tank from the passenger compartment on the Pinto. Remember how that ended? Burned alive inside their cars, can't get out--and it didn't take much of a collision to kill people.

WELD THAT HOLE SHUT, with reinforcements.
 
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Looks like my fuel pump went last Wednesday after work. It didn't really give any 'symptoms' of anything. I left work, got in my truck (97 C1500, 5.0L), started it up, and shifted into reverse as it died. I'm guessing residual fuel line pressure got me that far? As far as I know, it's the original 22+ year old pump. So I can't say I'm shocked. Checked the fuse, swapped the relay, even used a jumper wire to give the pump direct current. Nada.

Now my question is do I spend the $200 for the Delphi assembly, or $125 for a 'cheap' one? Delphi seems to be the best I can get in Canada. Probably worth it in the long run. Although I generally only put about 3,000km/year on the truck ... and I'm hoping to get about two years out of it before replacing 'er. Maybe the cheap route is worth it? Thoughts from anyone who's done it? I've heard mixed results with the cheap parts. Heading into winter here, I don't want to be futzing with the thing again at -30 in December or January.
 
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