Skip the auto shop - Our mechanics make house calls

Q: Gas gauge needle fluctuates up and down

asked by on

We just bought this car yesterday, it has 110,000 miles but was checked out by our mechanic and he gave us an excellent report. We had to put fuel in so we filled it up and drove 6 miles home. In that short period the needle fluctuated from full-over full to 3/4 a tank! I know these cars are supposed to get good gas mileage so what would cause the needle to do this? We are still within our 72 hours return so I am looking for a quick answer. Thank you!!!!
My car has a manual transmission.

This may possibly be a faulty fuel tank sending unit. This is a float type designed sending unit that sits inside your fuel tank that monitors the fuel level inside the tank. When this is faulty or failing it can cause intermittent changes in the fuel gauge to register as you describe.

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
  1. Home
  2. Questions
  3. Gas gauge needle fluctuates up and down

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: Is it mechanically safe to coast in neutral?

Technically, least cost operation is attained if engine idling (at stops) does not exceed 60 seconds and, indeed, some studies put the threshold as low as 10 seconds. Certainly 60 seconds is a conservative estimate. This is why "start-stop" features...

Q: Does the mechanic fix the ABS Traction Control problem, or just inspect and diagnose?

Hi There, Our experts here at YourMechanic are certainly able to fix any issues found when diagnosing the ABS and traction control system. As you may know, the traction control system monitors the steering and stability of the vehicle and...

Q: Used car question

The mileage is average for this year of vehicle. I would recommend having a pre-purchase inspection performed on the car before you purchase it by a mechanic like one from YourMechanic. The mechanic can check operation of all major systems...

Related articles

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 to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2103 OBD-II Trouble Code: Throttle Actuator Control Motor Circuit High
P2103 means there is a fault with the throttle actuator control motor circuit, likely due to a defective electrical component or part.