Fuel gauage

[Steven Sherard]

I have a 2000 K2500 standard cab Pickup, I have had the whole fuel pump assembly changed 6 months ago, My fuel gauge pegged out for a few days, then dropped down passed empty. It was accompanied by intermittent Service Engine light, no codes besides O2 Heating circuit malfunctioning. Any ideas what might this be?

[Jsdirt]

If I were to guess, I'd say 21st Century manufacturing has struck again. 

 

In other words, that "new" assembly is highly suspect - wouldn't be surprised if it has failed already. Before diving in there, I'd be looking for any wiring that may have been compromised during the install. If that all checks out, you'll probably be filing a warranty claim on that assembly, based on the last 5 years or so (even if the assembly is an OE replacement) .

[Steven Sherard]

Dang it, the part was OE, but the very first one died a week after install. This one that fail is the second warranty one...dreading dropping that tank for a third time in 6 month..dohh.

[Jsdirt]

Everyone is dealing with this problem. Every single shop out there deals with this on a daily basis.

 

I suspect this is the manufacturer's way to force people into new vehicles. Problem is, they don't understand that not everyone has $40 large laying around for a vehicle that will be a pile of scrap in just 12 years. Really poor investments ...

 

All that said, I would still test the wiring first before diving into the tank again - it could be a failed cluster motor for the fuel gauge, or a shorted, pinched / open wire.

[silveradosid]

if the gauge stays above full then the wires are shorted together no resistance if it is stuck below empty high resistance check the ground on the frame

[Jsdirt]

I always get this confused, since there are different specs for different brands ... however GM should be zero ohms for EMPTY and higher for full if I'm not mistaken.

 

Older Fords were the opposite, as is the industry standard.