Oil smell when ac on fresh air

I have an oil smell coming from my ac whenever any function of the system is run on fresh air and I'm idling. If I'm driving, I don't smell it, but as sooon as I stop moving, it's quite evident. Also, I don't notice any smell at all when the system is on recirculation. Anyone have any thoughts on a cause and more importantly, a fix? I have checked the cabin filter and it's fairly clean and free of any oil smell. Also, I don't see any oil on the ground that would indicate a leak. Any input will be greatly appreciated.

 

Recent oil change or service? Missing oil cap? Residual from oil change (won't drip necessarily) but will burn and smell horrible

 

No, unfortunately none of those. It's been going on for a little while.

 

What year truck? Could be a cam tower leak and oil is dripping on the manifold and you’re getting the smell.

 

I was going to say this exactly.....

 

I probably should have posted that initially, my apologies. It's a 2011, double cab, sr5 with the 4.6 under the hood.

 

You didn’t just finish a road trip with Tommy Boy who left the oil can under the hood?


Sorry, just adding some levity…

 

Are you burning any oil? Does it smell like burnt or fresh oil? Hard to tell, probably.

 

Not that I've noticed.

 

You may have done this already, but jack it up and crawl underneath it with a flashlight. Pull the splash pan (skid plate or whatever they call it) off.

 

No, actually i haven't done that, but I guess I'll add that to my to-do list.

 

Start it and pop the hood. PCV might not be working, or hung open. It will smell like burnt oil, if it is your PCV.

 

Did you check for cam tower leak?

 

No I haven't. Hadn't honestly even heard of that until I started this thread. I'm by no means a gear head. My knowledge of vehicle motors is pretty much limited to keeping fluids filled, changing plugs when needed and replacing the air filter. Beyond that, I really don't know much about what's under the hood, how to find /diagnose issues or fix them.

 

OIl and burning oil smell different, can you discern which you have?

 

If you can't smell it with recirc on, it is not in the cab, or at least not on the cab side of the cabin filter. We now klnow your cabin filter is working brilliantly. Engine compartment should not vent to your freah air intake, so somehing under there is showing himself. No noticeable increase in engine noise dB or character?

 

I can't specifically say it's a motor oil smell, but it's a petroleum smell of some sort, whether engine oil, or some other fluid, but I would not call it a burned smell of any type.

 

The only thing I have noticed recently is a puffing, leaking air sound, when I get in the throttle. I have custom exhaust and it's as old as the truck and has been leak prone over the last couple of years, so I've assumed it to be another exhaust leak I need to find. Other than that, which is directly relative to the amount of throttle I'm giving it, no new or increased sound.

 

There's something with the parts inside your air conditioner. By the way, this happens if you do not regularly clean your air conditioner or there is a problem with the compressor that blows out the smell of oil. In any case, I can help you by giving you the contacts of an experienced person who repairs air conditioners. He fixed my a/c in the summer for a reasonable price, and the quality of his work is high. He works for a company that offers air conditioning installation and repair services, so he has a huge experience. If you're interested, write to me in private chat.