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Old 06-18-2019, 11:43 PM   #1
KQQL IT
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More questions about our 99 crew cabbie

The fuel level gauge is getting the tremors.
The trip mileage goes to 9.9 and stops.

I've asked guys that do the newer cluster repair and they so no.

Any real options to fix either one?
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Old 06-19-2019, 12:58 PM   #2
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Re: More questions about our 99 crew cabbie

Pretty sure the fuel level gauge is controlled by the float attached to the pump. Based on float position, voltage will vary, indicating the correct position of the gauge needle.

While researching fuel pump/tank pressure/emissions issues in my truck, I saw a couple of different videos on YouTube where people said jumpy fuel gauge is bad sender on the pump assembly, or more common, the ground near the tank/filler is loose/failed/detached and the lack of solid ground is causing electrical issues.

Dunno where that ground would be on your crew cab, but on my 98 extended cab, it goes from the top of the tank to the framerail roughly between the filler neck and the forward-most driver bed mount bolt.

Being it's pretty cheap (free and quick) to check a ground strap, may be worthwhile. Beats pulling the pump and/or the cluster to check for grounding on those two.

I don't know if the gauge gets the voltage direct or by way of PCM. If it's via PCM, maybe a diag tool would let you probe the voltage to see if it's getting fluctuation, thus it's not the cluster that's the problem...
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Old 06-19-2019, 01:21 PM   #3
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Re: More questions about our 99 crew cabbie

Changed the fuel pump float sender assembly. No change to the erratic needle.
Turn the key on, and it will nearly make a 360 sweep before it settles down.
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Old 06-19-2019, 09:34 PM   #4
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Re: More questions about our 99 crew cabbie

Let me dig thru my hard drive. It's been years since I fixed my "hummingbird wing" fuel gauge on my 2000 K2500, but I usually keep notes on what I did.
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Old 06-19-2019, 11:50 PM   #5
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Re: More questions about our 99 crew cabbie

That would be great. Thank you
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Old 06-20-2019, 06:46 AM   #6
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Re: More questions about our 99 crew cabbie

First post here:

https://www.gmt400.com/threads/how-t...-needle.15139/

And read the last two post on this page:

http://www.pacificp.com/forum/viewto...=asc&start=140
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Old 06-20-2019, 09:40 AM   #7
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Re: More questions about our 99 crew cabbie

That's wild. I'd never guessed in million years that was an issue.

Thanks too.
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