2005 SX question OBD light
 

Thanks in advance for any help i may receive... About a week ago my OBD light came on and i lost acceleration RPM's wouldn't go above 2000 per gear. I checked manual and when i put gas in it went off and drove normally. This morning same thing again it only seems to happen when the gas gets just below halfway. I've read some of the other threads but no one else seems to mention fuel..... Any Ideas