Why would someone drill holes in this tube?

[bfarnsle]

The large rubber hose (like 3-4 inches in diameter) that is between the throttle body and the air cleaner.

There is a plastic hose that comes out of the top of this large rubber hose. It goes to the back of the engine.

3.1 L V6 97 Cutlass Supreme SL. I found 8 non standard holes drilled into this tube. You can tell it was done by someone. they are not uniform and you can tell that the holes were drilled because of the leftover plastic around the edges.

Why would someone do this? I think it has something to do with airflow. Thoughts?

Would this cause poor gas mileage? (That is my current problem since I am more than 10mpg under average for the car).

thanks,
brian

[SupremeCutlass]

The smaller hose that goes into the valve cover supplies air for the PCV (positive crank-case ventillation) system. The holes sound like they came from somebody who tried to increase performance, but had no clue what they were doing. I don't think it could hurt your mileage that much, unless perhaps the hose was clogged with plastic from drilling, stopping the PCV system, although as I said; I don't think that would cause such a radical drop in mpg. I would look for anything that's out of the ordinary that the person tried to do. Also make sure that you have a decent air filter, as some people will take it out to increase airflow although it can seriously hurt your engine over time (check for holes )