Hi DeltaFlyer,

The only time my Insight behaves like what you described is after a normal refueling - not topped off.
The FCD will become very easy to peg out, same speed I normally drive and get 80-100 mpg now becomes 125-140 mpg.

It doesn't last though, usually after 5-8 miles the readings return to normal.

If I do a FAS, I do notice the fuel gauge reading changes, normally reads lower after restarting.

Regards,