C4 Fuel Gauge Fluctuation
Thread Starter
2nd Gear
Joined: Jul 2025
Posts: 2
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From: Cabot, AR
C4 Fuel Gauge Fluctuation
I'm new to the Corvette world, specifically the C4 Corvette world. I've had a '90 Corvette base for about a year now that I tinker on from time to time. I've noticed when the fuel gauge gets to about 1/4 tank, it is not reliable at all. It will start off saying I have 150-160 miles remaining with the gauge at 1/4. As I drive, it may increase to 200+ miles remaining with the gauge going up to 1/2, then a short time later go down to reserve. Or it may start out at 150-160 miles then go down to reserve within a few miles of driving. Is this a product of '80s electrical engineering that I just need to learn to cope with, or is there a solution? I am sure this may have been covered at some point, and I tried searching the archives, but there were hundreds of threads that popped up on my search. I apologize for any redundancy.
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Probably the purple wire to the gauge is losing its connection. Remove the sending unit and resolder it, maybe replace the whole thing.
Instructor
Joined: Sep 2022
Posts: 121
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From: Tucson, AZ
It's a different electrical setup, but my 94 reads empty and "check gauges!" at 3 / 20 gallons left. Best thing to do if you're worried about range is fill up, drive, fill up again, do the math, and use the trip odo to keep track.
That said, vader's tip is also valid.
That said, vader's tip is also valid.
