SE low fuel light/gas gauge

[chevyconvert]

I have a complete new fuel system including fuel sending unit.

my gauge reads almost full (7/8) when I fill it up.

then I drive until the gauge reads close to empty (1/8) and my overhead console "low fuel" light comes on. Gas seems to go quickly, but it is a 440-6.

When I go to fill it up it only takes 10 gallons (18 gal.tank) to fill it up.

Does the low fuel light come on based on the gauge position or ?

Does this sound like a gauge problem or ?

[Bullitt-]

I don't know about the low fuel light but the incorrect gauge readings would be a classic sending unit problem. Either it's poorly grounded or the float is not correctly adjusted.

[Chryco Psycho]

I believe the low fuel light is tripped by the resistance off the sending unit so if the guage reads low the low fuel light will come on based on the same resistance reading the fuel guage works on

[chevyconvert]

the shop said that they ohmed the new yearone sending unit and it was ok, but the gauge tested bad.
Don't know how they can tell....

[71 DEPUTY]

Chryoco is right- based on resistance- once past a point a set of contacts trip inside the relay to turn on the light.  make sure gas tank has a really good ground. make one better than the stopid clip!
On my Chally I carefully drilled the locking ring where it is the most wide on the outside flange to fit a #6 screw and then to a nice clean piece of metal on the frame rail- drill it to a # 6 screw and connect with a couple of wire connectors- then coat it with a dielectric grease to keep the rustes away!!!!

John Mac

[ShelbyDogg]

Please don't drill on your gas tank. The clip will work if it's clean around the exit tube.  Check your float position like bullet suggested. If you have to, pull out the filler tube and look inside to see the float. Use a stick or coat hanger to move it all the way up while watching the guage.

[Shane]

When you have alow fuel light the gauge is powered by a separate power supply with a with thermal switch to tun on light. It is mounted over the glove box. It is possibly putting out incorrect voltage causing wrong reading at guage