I recently visited a mechanic who dismantled the air inflow pipes, air filter housing etc to get to the alternator to change it.. since then i have been gettin around 30 mpg instead of near 50!!

I decided to have a look just incase he forgot to fasten a pipe or it became lose, something that grabbed my attention was there is a pipe that was open ended? it took me by surprise so i took a picture.

the big pipe that goes from the air filter housing to the front of the car also seemed to be lose. Any ideas? is the pipe in the picture supposed to be open ended?

Thanks in advanced