I just cleaned my airfilter on my aftermarket intake. I noticed i was getting around 22 miles per gallon instead of 32 after i did it. I noticed the tube that goes from the valve cover to the intake tube was pinched shut. I just fixed it. I'm hoping that's what caused my crappy fuel mileage. Does anybody know for sure if this will cause poor fuel milage if you pinch that tube shut? I also just did my timing belt and i was thinking the timing may be off one tooth or something and then i saw this. I'm hoping that was the problem.

 

That's what it was. I just got 35 miles to the gallon after fixing the pinched tube going from the valve cover to the air filter tube. The pinched tube will cause crappy gas mileage, in case anybody wants to know.

 

yes because its also a way of recirculating unburned gas fumes

 

as a side note, high crankcase pressure can cause gaskets to go bad so check for oil leaks especially from the oil pan.

 

Pinched PCV tubes or damaged/clogged PCV valves are notorious for causing problems. It's a tune-up item often forgotten.