Air vent

Are you talking about the engine air intake?

I am ASSUMING this is a DP.

If DP, what is your air filter minder reading? That will tell you if you have a restriction.

The air minder was almost closed up and it’s got new filter in it an it it a class a rv

Then, yes, look at routing from filter to side of coach.

Many chassis are shipped with a long flexible hose so that the coach maker can locate the intake where they want to.

Often, this hose is WAY too long for the run and just shortening the hose reduces restriction.

Also, be aware that if the filter element has gotten wet, that really restricts air flow, so verify that your water drain is functioning/is open.

Has the air filter minder reading always been high, AND, did you reset it after installing the new filter?

You would need to post pictures of intake and hose routing for us to really comment.