[das boots]

I have an '03 Crew Cab Otto VG33 with 154K on clock. This smell started about a month or more ago. The smell will be there after a freeway run with the air vents turned on.

However, if using natural vents with windows crack open, there would be no smell.

There is a slight smell of exhaust gas when I open engine bay. There are no oil leaks leaking into hot pipes (As much as I can see). Oil has remained constant. No Check Engine Light (CEL). No smoke coming out of exhaust pipe.

Has anybody encountered this situation? Any help would be appreciated.

Thanks.

 

[shift_RUSH]

Is your in-cab rear sliding window open at all?
Will assume that moving vent to recirculate would result in no smell at all?

Either way, would be best to inspect whole exhaust system for integrity.

 

[das boots]

No in-cab rear sliding window.

However, after further evaluation, even when I do open windows a crack for positive ventilation with vent turn off, there is still exhaust gas smell.
But when I have all windows closed using natural air vent, there is not exhaust gas smell.

I think the gas might be coming from the otto transmission shifter.

You are right....I do have to inspect the whole exhaust system.

What would I be looking for?

 

[shift_RUSH]

Leaks!
Hope you find it soon.

 

[Nissan4Life]

First look at the whole exhaust system and look for anything obvious. Holes or gaps in joint. Next with the engine running listen for unusual exhaust noise. Exhaust leaks typically will give a short raspy "psshht" pulses. Suspect the header/exhaust manifold coming lose from the engine.

 

[luke9511]

i was getting the same thing and it was my driver side valve cover gasket leaking and burning off oil

 

[BigDad]

i was getting the same thing and it was my driver side valve cover gasket leaking and burning off oil

Same for me. It was so small of a leak, I didn't know it was the problem at first.

 

[AndysLog]

she wouldnt happen to be your girlfriend would she?


if so, please get out of the truck.

 

[invasion08]

I know around here, there are a few places that will do a free exhaust system inspection.

 

[jaymarstel]

Seriously dude get that checked asap! It's what you can't smell that can kill/harm you & passengers. Carbon Monoxide (CO) is odorless and deadly. As little as 8ppm (8 parts per million) can have adverse effects on human health.

Sent from my Pixel XL using Tapatalk

 

[paulforeman02]

Check exhaust manifolds/headers

I have a 2000 CC 4x4 V6 with 220,000 and the headers leak a bit and occasionally (with air vent open to the outside) I get a small whiff of fumes. As far as I have read and experience, it's a very common problem to have leaky headers on these. My brother in law had one for a while as well (2002) and his headers also leaked (especially passenger side). I haven't replaced mine yet but they're sorta hard to get at.

My solution has been to keep the air flow on re-circulate to avoid exhaust fumes in the cabin.

Good luck.

 

[das boots]

I have a 2000 CC 4x4 V6 with 220,000 and the headers leak a bit and occasionally (with air vent open to the outside) I get a small whiff of fumes. As far as I have read and experience, it's a very common problem to have leaky headers on these. My brother in law had one for a while as well (2002) and his headers also leaked (especially passenger side). I haven't replaced mine yet but they're sorta hard to get at.

My solution has been to keep the air flow on re-circulate to avoid exhaust fumes in the cabin.

Good luck.

Now that you mentioned it. Yes, I did take the Frontier to a muffler shop. They did an under carriage and muffler inspection. There was no exhaust leak detected. However, they did see a small oil drip on the drivers side dripping slow coming into the cat converter. I really do not know where is the oil coming from the drivers side. Do not know what is exactly above the cat that drips oil. At least now I know it is a slow oil drip. No wonder I do not see any oil stains in the driveway. Oil drip gets burned up by the cat.

BTW. I do exactly like close all windows to prevent positive air flow into the cabin from the shifter area and keep the ventilation on and on re-circ.

 

[Hertz]

Valve cover gaskets go bad on these engines. When that happens oil leaks into the exhaust manifold and/or the primary catalytic converters. It then burns and stinks. If you have a leaking valve cover and have verified there are no exhaust leaks then what you are smelling is burning oil, not exhaust fumes.

 

[RedDR]

Don't use recirc until you get the problem fixed.

Recirc just does exactly that so you don't get any fresh air.

Recirc off means fresh air comes in through the plenum at the base of the windshield.

If there's any possibility of an exhaust leak you want to bring as much fresh air in as you can, not try to keep it out.

 

[kevinjohnson3216]

Don't use recirc until you get the problem fixed.

Recirc just does exactly that so you don't get any fresh air.

Recirc off means fresh air comes in through the plenum at the base of the windshield.

If there's any possibility of an exhaust leak you want to bring as much fresh air in as you can, not try to keep it out.

I've always done the opposite, if I have an exhaust leak then I turn on recirc so that the exhaust leak coming from the front area of the vehicle doesn't get sucked in to the vents under the windshield wipers when I'm in traffic or sitting idling. No fresh air is better than exhaust leakage air

 

[Builder99]

You may want to check driver side valve cover gasket leaking... runs down on exhaust manifold and will cause a burning smell in then truck, especially if the cabin vent is open to outside air...doesn't take much of a leak, so you might not see it as a drop in oil right away...