I recently was under my car cleaning it from a stubborn oil leak (one I still can't find) and I noticed that the previous owner had taken off the top opti line and plugged it with a bolt. I put it back where it belongs but was wondering why it would be removed in the first place. Is this some "speed secret" I was not aware of or was he trying to mask a bigger problem. The car runs the same with the tube on or off.
Thanks guys.

 

Top opti line? Are you talking about a vented or non-vented opti? The vented opti has lines receiving air from the intake elbow, and a line going to the manifold.

Brandon

 

The vents [one in from the top of the intake elbow, one to the intake manifold thru a vacuum line[with a restrictor] ] remove moisture and ozone from the opti, by circulating metered intake air thru it, lessening corrosion, etc..
I'd hook that back up ASAP.. [no reason at all that it would be 'better' disconnected...]

 

I assume by your name that you have a 1994, unless converted, you don't even have a vented opti. Both vacuum lines go into the bottom of a vented opti.

 

This is my first 4th gen and I'm learning more about the car everyday. I don't know if it's been converted or even what an original one looks like. I can tell however that mine has been changed at some point and time. I hooked the line back up and everything seems fine. Just weird that it was dissconected and plugged