Fuel Senders
The fuel sender measures how much fuel is in the tank and reports it to the gauge. It uses a float on an arm connected to a variable resistor.
What it does
As the fuel level changes the float arm moves, altering resistance in the sender. The instrument cluster converts that resistance into the reading shown on the gauge.
Signs a fuel sender is failing
- A fuel gauge that reads permanently full or empty
- A needle that jumps around erratically
- A gauge that stops updating at a certain level
- A low fuel warning that never illuminates, or never goes out
When to replace them
Not scheduled. Replaced when the resistive track wears or the float fails.
What to confirm before ordering
Have these ready and the counter can usually confirm the part in under a minute.
- Whether the sender is separate or part of the complete pump module
- Resistance range, which differs between manufacturers
- Tank shape and arm length for the specific application
Fuel Senders questions
Why does my fuel gauge read incorrectly?
Most often a worn resistive track inside the sender, which is why the gauge frequently misreads around a particular level where the wiper spends most of its time. A float that has taken on fuel will read permanently low.
Is the sender replaced separately from the pump?
It depends on the vehicle. On many applications the sender and pump form one module and are supplied together. The branch will confirm which applies.