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Somethings Burning

My 2002 Mazda Millenia has a burning oil smell but only after coming to a stop after a hard run on the highway. The car runs fine otherwise. There is currently a code shown for one of the front catalytic converters (the car has three) but I was hoping that there is something else that could be plugged up in the emmissions system that could cause this. Any Ideas?

Just a slight chance,look for a plastic bag melted to one of the cats.Diagnois this plugged cat with a manifold vacuum test,stay on this problem,time is running out for you to get a free cat on the Federal Warranty regarding cats. (8 yr 80,000)

Yeah, I had the plastic bag problem once. It took over a week for the smell to go away.

It’s possible you have a slight leak in a valve cover gasket or another seal (like a main bearing seal) that leaks only when under pressure for a while. You could pop the hood and look for traces of oil/oil smoke after a ‘hard run’ Also check your PCV system—if it’s malfunctioning, it may be letting pressure build up and push oil through engine seals.

I like this idea. You smell it after a hard freeway run because it’s been leaking oil more rapidly while you’re running it hard, but the smell is just blowing away without you noticing it. When you come to a stop, the smell wafts in to the vents.