Fuel gauge question
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Melting Slicks
Joined: May 2019
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From: Mid-Atlantic
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Fuel gauge question
The last time I filled up the gauge looked ot be around a quarter of a tank.
So I put 50 dollars in the tank and the pump shut off at 49 dollars. I ended up squeezing that last dollar in there, but at almost 5 dollars a gallon, the 50 dollars only gave me ten gallons.
Anyway, I'm thinking maybe a half of a tank of fuel might look like a quarter of a tank on the fuel gauge.
But I'm not exactly sure.
There is that half way line on the gauge, but it actually read around a quarter of a tank before I fueled.
Does anyone know if that's a fairly common thing for the gauge to read around a quarter of a tank even if you have a half of a tank?
I can probably check the ohms and recalibrate the thing but if the gauge isn't known to be exactly accurate, I'm not gonna bother with itright away.
Mainly because I have more fuel in the tank than the gauge actually reads.
Thanks for any input.
It's a '90, btw, so not the old style C4 gauges.
So I put 50 dollars in the tank and the pump shut off at 49 dollars. I ended up squeezing that last dollar in there, but at almost 5 dollars a gallon, the 50 dollars only gave me ten gallons.
Anyway, I'm thinking maybe a half of a tank of fuel might look like a quarter of a tank on the fuel gauge.
But I'm not exactly sure.
There is that half way line on the gauge, but it actually read around a quarter of a tank before I fueled.
Does anyone know if that's a fairly common thing for the gauge to read around a quarter of a tank even if you have a half of a tank?
I can probably check the ohms and recalibrate the thing but if the gauge isn't known to be exactly accurate, I'm not gonna bother with itright away.
Mainly because I have more fuel in the tank than the gauge actually reads.
Thanks for any input.
It's a '90, btw, so not the old style C4 gauges.
Pro
Joined: Apr 2020
Posts: 626
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From: Chicago
The last time I filled up the gauge looked ot be around a quarter of a tank.
So I put 50 dollars in the tank and the pump shut off at 49 dollars. I ended up squeezing that last dollar in there, but at almost 5 dollars a gallon, the 50 dollars only gave me ten gallons.
Anyway, I'm thinking maybe a half of a tank of fuel might look like a quarter of a tank on the fuel gauge.
But I'm not exactly sure.
There is that half way line on the gauge, but it actually read around a quarter of a tank before I fueled.
Does anyone know if that's a fairly common thing for the gauge to read around a quarter of a tank even if you have a half of a tank?
I can probably check the ohms and recalibrate the thing but if the gauge isn't known to be exactly accurate, I'm not gonna bother with itright away.
Mainly because I have more fuel in the tank than the gauge actually reads.
Thanks for any input.
It's a '90, btw, so not the old style C4 gauges.
So I put 50 dollars in the tank and the pump shut off at 49 dollars. I ended up squeezing that last dollar in there, but at almost 5 dollars a gallon, the 50 dollars only gave me ten gallons.
Anyway, I'm thinking maybe a half of a tank of fuel might look like a quarter of a tank on the fuel gauge.
But I'm not exactly sure.
There is that half way line on the gauge, but it actually read around a quarter of a tank before I fueled.
Does anyone know if that's a fairly common thing for the gauge to read around a quarter of a tank even if you have a half of a tank?
I can probably check the ohms and recalibrate the thing but if the gauge isn't known to be exactly accurate, I'm not gonna bother with itright away.
Mainly because I have more fuel in the tank than the gauge actually reads.
Thanks for any input.
It's a '90, btw, so not the old style C4 gauges.
Pro
Joined: Jun 2008
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From: Louisville Kentucky
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Change the sending unit and pump. it's easy to do.
Safety Car
Joined: Mar 2017
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From: LeClaire Iowa
All the replacement sending units don't seem to be as accurate as the original when new. I replaced mine and while WAY better it is still not perfectly accurate. I have read about people who have bent the arms while reading the ohm output and got it spot on. I did not do this. Dan
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Melting Slicks
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Melting Slicks
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At the moment, it's reading less fuel than I actually hae, so may just let it ride for a while.
Was just curious if others experienced this mainly. Thanks.
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Melting Slicks
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I have had the same “more fuel than the gauge shows” experience with both the original pump and sending unit and the NOS replacement pump and sending unit I had put in last year. Somewhat accurate, but I always set the trip odo just in case. I don’t think it is the gauge, because when I replaced the pump but not the sending unit, the gauge read full all of the time. Once I changed the sending unit, the gauge started reading again.
Drifting
Joined: Feb 2016
Posts: 1,384
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From: Simi Valley CA
When I fill mine it seems to stay on full or at least the top 90% for about 100 miles. Then it will go down to a quarter in the next 100 miles and then from quarter to empty has about another 100 miles. This is how all my Chevy fuel gauges behave.
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From: LeClaire Iowa
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I replaced the fuel tank last year.
After I installed it, I put two gallons in it, then drove to the station and filled it. Think it only took 17 gallons at the station. Adding the previous two to that it was 19. So not a full twenty gallons. Not unless the two 1 gallon jugs were slightly over the gallon mark.
I did just go for my evening cruise on a full tank and when I was driving up the steep grade back road, it still dropped a couple of bars. The road is slightly greater than a 45 degree for about a quarter mile. When I leveled out, it went back to reading full again.
After I installed it, I put two gallons in it, then drove to the station and filled it. Think it only took 17 gallons at the station. Adding the previous two to that it was 19. So not a full twenty gallons. Not unless the two 1 gallon jugs were slightly over the gallon mark.
I did just go for my evening cruise on a full tank and when I was driving up the steep grade back road, it still dropped a couple of bars. The road is slightly greater than a 45 degree for about a quarter mile. When I leveled out, it went back to reading full again.
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Melting Slicks
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Drifting
Joined: Feb 2016
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From: Simi Valley CA
The gas station nozzles won't actually fill until you're 100% full. The nozzle senses a certain pressure and clicks off. I have often filled 2 gallon jugs. I get pretty close to the 2 gallon mark and the pump reads 1.75-1.8 gallons. I have topped it off before only to get to the 2 gallon mark and have the pump read 2.3 gallons. So topping off actually shorts you on fuel. When you click the pump back on there is that brief moment where the pump is spinning but no fuel is coming out. When filling your tank that's .1 gallon or less so no big deal. In clicking it several times to get that .2 gallons it adds up.