Skip the auto shop - Our mechanics make house calls

Q: After fill-up, gauge went to top, then dropped to middle and stuck there

asked by on

The last time I filled up my Mazda, the gauge went all the way to top about 15 minutes after fill-up and then after driving about an hour, it dropped to middle and stuck there. How do I fix this?

The fuel sending unit inside the fuel tank uses a variable resistor unit to control the fuel gauge. If the sending unit is faulty then it could fail in any position, causing the gauge to not work correctly. A true test is to remove the sender and check the resistance of the sender while moving the float up and down. If it does not match the specification, then it should be replaced.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!
  1. Home
  2. Questions
  3. After fill-up, gauge went to top, then dropped to middle and stuck there

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: fixing an ignition. switch to a mozda rx8 year2004

The instructions are set forth in the Factory Service Manual and in the case of the lock cylinder (the lock cylinder is probably the part that was drilled, not the switch itself, which is behind the cylinder) they are detailed....

Q: losse of heat when going 70.

Hi there. I have come across this same problem several times. The majority of the time it is caused by a failing thermostat. Due to the poor design of a metal thermostat molded into a plastic housing these will not...

Q: Can't figure out what's wrong with my car?

Hello, thank you for writing in. The vehicle may be suffering from several different issues. One of which is spark, and replacing the spark plugs was a great start. Secondly to the plugs however, are the spark plug wires and...

Related articles

How Long Does a Heater Control Valve Last?
Keeping the right amount of coolant in a car is essential in keeping the engine at the right temperature. Failing to have the right amount of coolant or even bad elements...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.