Inaccurate fuel gauge
- Thread starter mayorj1227
- Start date
Usually, it's the other way around.
Gauge gets to E and there's still a few gallons left.
How long was it at 1/4 tank? Not a Jeep but I had a Volvo that would get stuck at about 3/8 and the needle would just sit there until empty. A lesson I only had to learn once.
The gas gauge on my 97 TJ showed empty today, fuel light on and gauge on the E empty, drove up to the gas station and filled it up, 15 gallons in a 19 gallon tank… there was 4 gallons left in the tank… these gauges are notoriously inaccurate!
KennethS
TJ Addict
Same as mine. When the gauge hits E and the light comes on there’s still 5 gallons in the tank.
And after a fill up, the gauge drops to 3/4 after around 50 miles. So I use the odometer along with the fuel gauge to know when it’s time to stop for gas.
And after a fill up, the gauge drops to 3/4 after around 50 miles. So I use the odometer along with the fuel gauge to know when it’s time to stop for gas.
KennethS
TJ Addict
Thread title is “Inaccurate fuel gauge” and he asked “Anyone else?”
I had this happen to me in a YJ that I had once. My tank had collapsed some because of chunks of dried mud that had gotten between the cage and the poly tank. Cleaned out the mud and it added about 4-5 gallons of tank capacity and no more running out of gas at 1/4 tank.
Mines done that since I bought it. I've been told I can fix it but I'd rather just refill when it's on E.
Inaccurate isn't the word I would use. Maybe "unintuitively scaled". The needle will go as far past E as it goes past F when you fill it up.
The pump won't stop at 15 if you push it this far - I actually got 17.8 gallons into it on this one. In my defense I entered a 45 mile stretch of no fuel stations without realizing how low I was.
Based on some notes I made on a road trip (uninterrupted highway cruising between fillups, on a separate occasion from the above photo), it seems like half a tank is likely pretty close to half a tank, there's probably 3 gallons above the F, and likely 3 gallons below the E. My light seems to come on with about 3.75 gallons left as almost 50% of my fuelups are near an average of 15.25 gallons. Clearly I did not listen to my dad when he advised me to avoid letting my tank go this low.
I noted the mileage at each "landmark" on the fuel gauge, constrained the light coming on at my seemingly statistically supported 15.24 gallon average fillup from the light coming on, and then interpolated the points in between full and the light coming on, then extrapolated the predicted E marker fuel level and true empty mileage.
Now after that tangent...
I agree. I believe the float is likely sticking or something is electrically amiss in the potentiometer that turns the float level into the voltage read by the PCM.
From the owners manual:
22. Low Fuel Warning Light
When the fuel level reaches approximately 2 U.S.
Gallons (7.6L) this light will come on and remain on
until fuel is added. The “Low Fuel Warning Light”
may turn on and off again, especially during and after
hard braking, accelerations, or turns.
24. Fuel Gauge
The pointer shows the level of fuel in the fuel tank. When
the fuel gauge pointer initially moves to E, for your
safety, approximately 2 U.S. Gallons (7.6L) of fuel remain.
I take this to mean you have four gallons left when the light comes on and two gallons left when the gauge hits the E. Which seems to be the case as I can add 15 gallons when the light comes on.
22. Low Fuel Warning Light
When the fuel level reaches approximately 2 U.S.
Gallons (7.6L) this light will come on and remain on
until fuel is added. The “Low Fuel Warning Light”
may turn on and off again, especially during and after
hard braking, accelerations, or turns.
24. Fuel Gauge
The pointer shows the level of fuel in the fuel tank. When
the fuel gauge pointer initially moves to E, for your
safety, approximately 2 U.S. Gallons (7.6L) of fuel remain.
I take this to mean you have four gallons left when the light comes on and two gallons left when the gauge hits the E. Which seems to be the case as I can add 15 gallons when the light comes on.
