re you slow car. sometime bad linage will cause the car to not get full fueling.
Check that your linkages for from the fuel petal to the ip are all working and adjusted corectly. IE if you push the pedal to the floor does your link on the ip hit the stop. watch the linkage on the fire wall to see that it does not flex and lose some of the movement that should be transfered to the ip.

Re you oil loss, are you dripping or burning or blowing it out the exhaust?
check the blowby by loosening the oil fill cap and then letting it sit on the hole. Will it sit there or is it blow off by the preasure ? if blow off you need to diagnose the problem with a compression test and a leak down test.
also you can lose a fair amount of oil from bad valve seals which are relatively cheap and easy to replace.
JJM