I get out of my car after driving it and I smell like I've been doing oil changes the whole day. This started about 3 months ago. I think it is originating through the AC and heat vents. How do I get rid of the smell? Where do I spray the cleaner/odor neutralizer into the system to get rid of the smell?

Oil level is fine, and I change it every 5K miles.

Any suggestions? I already Febreezed the *#&$ out of the carpets and mats!

Check that the seal in front of the air intake against the hood is intact.
If its not there you will use air from the engine compartment :)

First, you have to find out where the oil leak is. Probably a small leak from the turbo oil return line and dripping on the exhaust.
The cabin air intake is under the hood, just below the windshield. If you remove the plastic shelf, lots of torx screws, you will find the cabin air filter. Change it.

Klaus
--
(1975 164, 1995 854T, 1998 V70R)

No, on S80s the cabin air filter is under the left side of the dash, not under the hood like X70s.

How do you change it out?

Remove the right lower hush panel (2 screws), remove the 4 screws to the rectangular cover on bottom section of housing, slight filter downwords.

ooops.....meant "slide" not slight (too early).

I'm having this issue too on my '99 S80, but I've been told it's the flametrap (or whatever it is in this car). It's under the intake manifold.

The oil smell has NOTHING to do with your cabin air filter. You're smelling burning oil because there's an oil leak and it's most likely burning on your exhaust pipes as another poster said earlier.
The S80s do NOT have a "flame trap" as earlier models did BUT has a known issue with bad (PCV system) breather box seals which leak oil on the front side of the engine. The breather box is the large black thing under the intake manifold.
If it's a T6 S80, then besides leaking breather box seals, the turbo drain tube o-rings are another common source of oil leaks.
If someone added oil too fast to the fill cap during an oil change, oil will spill out all over the top of the engine and go under the plastic cover. It can then spill out and drip all over. Just another possibility.
IF in doubt, degrease the engine, add oil dye, drive the car and re-check for the source of the leak(s).

Just got off of the phone with the dealer. They told me $175 turnkey to replace the o-rings on the turbo. I do not have a T6 S80, just the regular S80. They told me that even though I don't have a T6 there is still a lower pressure turbo on the engine.

Are the o-rings easy to replace? How much time and special tools do you need?

I think you must have misunderstood the person on the phone, or they were misinformed. Do you really believe Volvo would have installed a turbocharger on the 2.9, yet their Marketing folks decided to keep it a secret?

Perhaps someone thinks the EGR valve is a turbo because it connects between the exhaust and intake.

I re-emphasized it when I talked to him that it was not a T6. What I write is pretty much verbatim to what he said. So where would the source of the burning oil be now that the "low power turbo" is not the issue? Do I need to pull off the aluminum panel above where the braided exhaust pipes go into the engine and look around for a leak?

I'm pretty frustrated and just want the origin of the smell to go away.

Whoever you spoke to has NO idea of what they're talking about, probably a receptionist or inexperienced service writer who knows NOTHING technical about Volvos.
Your non-turbo 2.9 S80 has NO turbo or turbo return line, period! There IS yet another possibilty, there's a metal freeze plug that goes into the holes in the block where there would be turbo drain tube returns (IF turbo) and sometimes they blow out. One needs to look up there with a mirror to see if a plug blew out.

Don't guess, take the car in and have its leak inspected by a tech who's familiar with Volvos. Even though the person you talked to on the phone doesn't have their facts straight, odds are good that the techs there do know better.
Btw, there's also NO EGR valve either as another posted suggested.