I got a brand new rock auto spectra premium fuel ranging unit with my custom wally 450
it works mint
and the car is full off gas to the point of me tricking down
and the fuel gauge reads 2/3 full
i did drain the gas and the float worked a crack below zero was empty
the full point is 2/3 full
does anyone have help
I paid way more for the spectra brand
I still have the stock sender
it still works

help me

 

I need help ppl

 

The first suspect would be the sending unit resistance range There could also be mechanical interference preventing the float and arm from moving freely. Unfortunately, those are easiest to test with the sending unit out of the tank and/or tank out of the vehicle.

After that, wiring and grounding for the level sensor and gauge could be checked.

 

Yep... Would always be good to test before tank installation...

The sending unit can be tricky and I have seen the arm get bent... In my car it read half tank when it was empty!

 

I had a similar experience. I finally "fixed" it by adding a resistor in series with the sending unit signal wire under the left rear seat. Seems like I got 80 ohms on a full tank, and it should have 90 ohms. I'll have to check to make sure, but I believe I added a 10 ohm resistor (one of those big ones they sell to add resistance to LED light circuits) and it now reads very accurate. When I fill the tank, it goes to just a hair over the "F." However, I imagine when it reads "E" it will be REALLY empty. It takes about 13 gallons to fill when it gets down to the "hashed" area on the gauge between 1/4 and E.

 

Stock 1989 L98 GTA, just replaced the pump, strainer and sending unit due to a pump having issues. Old sender read high on full and actual empty was about 1/4. New sender reads 3/4 tank when its full.

I purchased one of these Meter Match units from Tank. I believe it will resolve the issue quite nicely.

With my gauge reading low at actual full this seems to be a good choice. If the gauge were reading high at actual full an inline resister could work.

The plan is to wire it under the dash near the drivers side kick panel. I used a similar one in an old Impala and it worked great.

Tank Meter Match

Will give some feedback once I receive it and get it installed.

Gerry-

 

That looks pretty slick.

Sending unit should show 90 ohms when tank is full; 0 ohms when empty. If gauge is reading lower than it should with a full tank, the sending unit resistance is too low. IOW, if the gauge reads 3/4, it's seeing ~68 ohms (90 x .75) regardless of how much fuel is in the tank.