My car is getting terrible gas mileage, under 10 mpg, I think. My last tank got 14.5, before that 17.2, before that, 18.0, and before that consistantly 20-22. I just changed the spark plugs and O2 sensor, TPS is at 1k ohms, car has no loss of power of any kind.
I thought it must be a fuel leak, probably the FPD. I hooked up the jumper wire at the yellow plug to engage the fuel pump and turned on the ignition, but there were no visible leaks, and no trace of a gas smell anywhere. I'm stumped. Ideas, anyone?

 

random guess: injectors

 

The spark plugs look perfect, no fouling whatsoever, if there were excess fuel getting into the engine the plugs would be fouled, so it can't be an injector. So where is my fuel going?