Ok, so all JKs have varying degrees of what I'll call "engine smell" in the cab. Some smell less, some smell more, most smell heavy under WOT. Most people know you can turn it on floor + recycle to get rid of most of it. That doesn't really fix it though.

So, I had a thought, what if you could pull fresh air from somewhere else to the intake for the vehicle? Then, I realized, I have NO idea where the intake is ... so that's my first question ... anyone know where that is?

From there, has anyone tried it and had success or failure?

Thanks =)

 

The fresh air intake for the cabin is through the grill just in front of the windshield.

Regarding "all JKs have varying degrees of what I'll call "engine smell" in the cab", how can you know that?
Mine doesn't have it. The JKs I've been in don't have it.

If you are getting odors from the engine bay, look for openings in the firewall or the forward floor section.

 

My JKU (27K now) has had an odd burning-like smell under WOT at high revs (above like 5K) since it was brand new. I thought at first maybe there was some coating or residue on the exhaust that would eventually burn off and stop doing this but it persists now for over two years. This, plus the transmission noise it's also made since new, are among things I have considered having them look at before the warranty is out.

This is the first I've heard that this "smell" is anything besides unique to my Jeep.

 

There's literally hundreds of forum posts about it. Google "jk engine smell" or similar.

I'm in a Jeep club with a dozen JKUs. All owners complain about it.

I'm considering a project of dynamat+bedliner anyway, and that'll force inspecting all openings, but from casual glance and knowledge of my rig, all grommets are in place.

If I turn off the blower and turn it on recirculate it goes away so its coming in the vents. When you turn on recirculate, it closes the flap that lets air in from the engine compartment. I may install an air filter behind the glovebox at the blower. Maybe it'll cure some of it. Either way, its clearly coming from the engine.

It's possible that my situation is worse due to my hood scoop which could be venting towards the intake there. I may need to get creative with this.

 

I was going to ask if you had something like that until I read your edited post.
Scoops in the hood that face the windshield should be sealed into the engine intake system. After all, their purpose it to take advantage of the high pressure zone in front of the windshield.

 

I will give you my experience around this engine smell. I haven't googled that particular phrase so I don't know how prevalent it is, but I experienced what I would consider the same, or similar, situation.

Under not necessarily WOT, but heavy pedal, I had a smell since almost new I thought was residue or tape or something. 14 JKU. Took off engine cover and did find some sticky stuff there. Removed it with no change. Ended up just believing it to be hydrocarbon build up burning off.

Sometime later I was under the Jeep doing work and saw fluid seemingly coming from my transmission. Started looking into this and I came across the oil filter housing issue threads. Checked out mine and lo and behold I had oil sitting atop my engine. Took it in and was fixed under warranty. Guess what? No more engine "smell." So for me, that was the cause. Maybe look into this on yours.

Just in case you want a little more evidence, next oil change I did at the dealership after the fix. So I had no smell for 5k mikes, then it came back. Just looked recently and there is oil on my engine again. Going back this week AGAIN for a filter housing replacement. Seems cut and dry to me.

 

Well in my case it's clearly not an oil smell and literally it has done this since the day I drove it off the showroom floor. Jeep had like 9 miles on it when I took it home. It had never had an oil change. Unlikely this was cracked from the factory. But anyway, I've done like 3 oil changes (myself) and there's no oil on top of the engine, never has been.

I wish I knew what was causing the "engine smell" (almost a burning smell) that my Jeep does, and it'd be encouraging to know that others have the same thing.

I still think there's a pretty good chance it's something actually burning off. Maybe one of those ridiculous bar code decals that Chrysler sticks on every single flippin part. I mean, there's got to be one of these stickers on each header, on the catalytic converters, on the Y-pipe, on the midpipe/resonator, on the muffler, etc. I have yet to see any part in my Jeep that doesn't have one of these stickers on it.

Or maybe there's a sticker on some other thing that happens to come into contact with something hot like the exhaust.

BTW mine's probably not just WOT it's just that rarely do you rev >5K unless you are WOT. And the rental Jeeps (2016s) that I drove in Hawaii didn't seem to have the smell. But maybe it's because I have the drains out? Maybe something is leaking in and I can smell it because all of my drain plugs are out? Could be a dozen things I guess. I've always had the drains out... well I took the carpet and drains out like 3 days after I bought the Jeep.

 

Mine smells of cigars. Now the engine bay that is another story. Coolant galore.

 

What year of JK do you have?

In 2011+ JKs, FCA added a cabin air filter which is located behind the glove box. You may want to try changing that.

 

I had the exhaust smell from a cracked exhaust manifold. Replaced it and that went away.
Three weeks later that one cracked. Smell is back. I'll just call it air freshener.