Engine Performance problem
1997 Toyota Corolla 4 cyl Front Wheel Drive Automatic 142000 miles
----------------------------------------------------------------
Are all 3 vaccumn ports on top of the throddle body suppose to be open to blow through? I am having aproblem with a clogged port some where that is throughing a check engine light. I replaced egr valve, vaccumn switch, and egr valve assembly. Somene found that and said all 3 vaccumn ports where ever they go are always to be clear

Hi dlehman,

The vacumn ports should be open if there are hoses attached to it. Only difference is that the flow rate might be different. You should be able to test by connecting a hose and blowing with mouth.

If any is clogged, the throttle body most probably requires cleaning.