On my 2008 RX350, with fresh air turned on, I get "hot engine" smell from vents. Not gassy, just smells like under hood normal smell. But its coming through the vents. On recirculation mode, no smell is present. Any ideas?

 

I'm not trying to be funny, but something's broken--likely a seal or weather-stripping--somewhere. Lexus & Toyota usually do a reasonable job of sealing off the engine compartment & the associated smells from the vents. I would look around under the hood, back by the firewall & if you don't find/fix it, get ready for a trip to the dealer.

 

I'll give that a look! Thanks!

 

Be careful about going to dealer, there is a lot of HVAC stuff tucked under the dash, and it requires the whole dash, steering column, basically the entire front inside of car to be removed to get at it. (Google RX350 replace expansion valve on youtube for some horror pics) Just a heads up, hope the problem is on the engine bay side.

 

I learned a trick from a body shop friend of mine. I put a small (3/8") foam round "rope" into the main long gasket sealing the back of the engine bay. This expands out the gasket for better sealing. I think its better, but the smell it still there. All the gaskets seem to be in place... Thanks for the info, I'll keep working on it!