F-150 fuel indication

[Bender]

I have a 2001 F-150 bi-fuel. I've noticed that it indicates slightly less CNG on the fuel gauge than when drove it last. It seems more noticable when the CNG tank is less than half full.

I'm pretty sure I don't have a leak. I 've parked it for over a week before on a full tank and it seemed to still be relatively full. Also, I'm aware that temperature can make a difference.

Recently I drove about 50 miles on the bottom half of my tank. When I parked the truck it indicated 1/4 full. About an hour later I went to drive it again and after starting it indicated a little over 1/8th.

It's almost like the start gobbles up a whole bunch of natural gas.

Any ideas?

[darress]

Re: F-150 fuel indication

Hello, I believe it's a combination of temperature and pressure, like you mentioned, along with an imperfect system for converting the signal for the gauge. In my truck I see about 75% of the total mileage below the 1/2 tank mark. The gauge readings are very inconsistent and I can't ever get it all the way to "full" even with a great fill.