P0300 Cadillac - the power goes away when driving up hills and i'm loseing lots of gas

Question

Whats' going on with the car when I am going up hill, I lose power and I seem to be burning a lot of gas?

Answer 1

P0300 Random misfire

P0420 Catalyst system below efficiency

P0442 Evapostaive emission control system leak detected (small)

Check the basic such as the airfilter, tune-up such as when was the sparkplug changed? 

Here is a Cadillac that the owner complained of no power and being very sluggish especially going uphill, and using alot of gas. Doing the basic check revealed the problem this is the airfilter .plugged. Clean out the airfilter housing replace the airfilter perfromed a tune-up put this Cadillac back on the fast lane.