96-2000 Fuel gauge

[GasGuzzler]

They pretty much don't until 2000 or so (some 99 half tons do). The 2000 model 2500's don't either and even some of the mid 2000's GMT800 body 2500's don't have it.

Ooops...I stand corrected. I see now that some 98's have one too. I looked in a different place in service information and it didn't list it. Hahaha there is reference to this sensor on the 97 too but no replacement instructions. Boy I love depending on faulty and imcomplete information from GM to make a living. I'll go out on another limb and say the 96 does not have one.

[Wtfan18]

hmm well im going to check all my connections first to make sure its not a bad ground or a bad connection, then i guess i will try a new sending unit from a 97.

[NITROUS]

I've worked on quite a few of the 98's and they do have the FTP sensor and it's also in the Alldata cluster schematics per California emmisions. The problem with the fuel gauge on the 98 is the fuel sender is 40-250 ohm and goes directly to the PCM C3 connector and out the C1. There's also a 5v return for the FTP sensor. The 97 is 0-90 ohm and goes directly to the gauge. I'm running a 2000 Denali 120mph cluster in my 97 and it works fine. The only way for the 98 to work is to change the sending unit out to a 96 or 97 and start from there. Sorry I didn't tell you this i the PM but I was thinking 97 Wtfan18.

[NITROUS]

wtfan18, go buy a sensor and unplug your on top of the tank. If you have enough wire plug in the new sensor without dropping the tank and test it to verify the gauge by sliding the rod up and down the resistor.

[beater6.0]

he will still have to bypass the pcm conn. only two wires dont rember the colors though

[GasGuzzler]

Thanks Lance I already admitted by dumminess

[NITROUS]

No, you actually know quite a bit and I didn't see your edit. .

[Wtfan18]

well after almost running out of gas again last weekend i decided enough is enough. i was about to break down and buy a 97 sending unit when i realized the donor parts truck that my sending unit and fuel pump are out of is a 97 and not a 98 like i had thought so i dont need to buy a new unit i just need to know how to bypass the pcm and get my guage working! anyone have any way they can describe what needs to be done here? i really just want to fix the issue. it sucks not knowing how much gas i have...

[Lextech]

If your truck is a 98 then the stock 98 fuel pump/sender module WILL WORK your fuel gauge. From your original Black PCM connectors--98 C1-9 Purple wire will go to 02 C2-38. 98 C2-26 Black wire will go to 02 C1-23. 98 C3-13 Purple with White stripe wire will go to 02 C2-54. It will work. The 02 PCM #12200411 has been installed into dozens of 98-2000 GMT400 (Old Body Style) trucks.

Jeff

[Wtfan18]

If your truck is a 98 then the stock 98 fuel pump/sender module WILL WORK your fuel gauge. From your original Black PCM connectors--98 C1-9 Purple wire will go to 02 C2-38. 98 C2-26 Black wire will go to 02 C1-23. 98 C3-13 Purple with White stripe wire will go to 02 C2-54. It will work. The 02 PCM #12200411 has been installed into dozens of 98-2000 GMT400 (Old Body Style) trucks.
Jeff

right but i have a donor fuel pump and sending unit from a 97 gmc sierra 5.7liter vortec because i had a 4.3 pump before and it wasnt enough, will your method work with a 97 sending unit and 97 fuel pump or just the 98?