I had my transmission rebuilt back in Feb. and since then my fuel gauge has not worked properly. I fill up and it shows full but when I start driving the gauge starts to drop between the full and 3/4 mark. If I am at a 1/2 tank then the gauge drops between 1/4 and empty mark and sometimes all the way past E. What could be the cause of this? Also my low fuel light does not come on when I am low on fuel......any suggestions would be helpful. Thanks...It is a 91' Honda Accord Ex Coupe. I was told to replace the fuel gauge sending unit. I did that and it is still doing the same thing.......any other suggestions? Do you think it could be a wire connection or sensor?

Thanks.......

 

tranny job shouldn't have affected the fuel gauge.

I had a similar problem with my 94 a few months ago. my needle would drop out past E, then rise back later when it decided to. My problem was the sender though. it had three wires, two for the sender and one for the low fuel light if i remember right.

check the operation of you fuel gauge itself by unplugging the sending unit and inserting an appropriate resistor across the two leads for the sending unit resistor. this will mimic the sender in the tank. you will need to know which two wires are for the sending unit.

empty (on my 94) is 105-110 ohms, 1/2 tank is 26-40 ohms, and full is 3-5 ohms.
i bought a 33ohm resistor (and some others) from radio shack and pushed the two leads into the harness connector for the tank sending unit. i then turned on the key and watched the needle rise to 1/2 tank, then i drove it with the resistor installed for a couple days. all was well, so I determined the sender in the tank was acting up. been fine ever since.

if you still get the problem with the resistor inserted in the connector, you have a wiring or gauge issue. this will rule out the sending unit you installed. the wiring is probably okay if your needle is moving since none of that wiring should be broken. check to see if anything has rubbed through the insulation from the sender to the gauge. if you havn't had any fuses blowing, there should not be a short to ground.

I'd run this test and see if you still get a fluctuating needle.

you may need to replace the gauge. you could take the gauge out of the cluster and bench test it with a fused power wire and a few different resistors, but that will be an involved test.