Hi all,

I have a 2000 Civic EX, 2 door. I've noticed that directly after a fill up, the gas gauge will just barely kiss the 'full' mark, then drop rapidly, almost as if the tank didn't fully fill. I've taken the fuel sending unit out and tested voltages - it's fine, and when manually placed to 'full', the gauge moves to full as well. That demonstrates that the gauge isn't broken either.

That leaves me with a couple possible options. Either my fuel sending unit is physically impeded inside the gas tank from fully raising, or there's some evap issue resulting in an inability to fully fill the tank. The second option is my suspicion, because I feel that I only get about 9 gallons of range out of the tank, where I should get at least 11 (before the low fuel light comes on).

Any knowledge of evap systems and what I might check? Perhaps a broken valve or clogged vent? Your help is much appreciated.

Thanks,
Rob

 

The fuel sending units in our cars suck.

My original sending unit worked okay (for a Civic), but the low fuel sensor died.

I bought a new sending unit from Honda. It didn't fit quite right in the tank of my bone stock 97 Civic. The low fuel warning light now works fine, but the gas gauge now never quite reaches the Full reading and the needle drops more quickly than expected, as your does, despite the fact that the avg gas mileage has remained the same forever.