Smelling exhaust or gas while driving.

[moonlitcoyote]

For the first time in the last 5 days of driving, I smelled either exhaust fumes or gas while driving today. It was very strong at times to the point where I had to open all the windows. I am pretty sure it was exhaust and not gas but you can never be certain I guess. The gas gauge didnt change anymore than usual so I dont think I have a gas leak. My doghouse is not bolted down but never has been so not sure if that would be the problem. Does anyone have any ideas or suggestions? I hate to be smelling it all day tomorrow too. Thanks.. MJ

[Oz]

I'm sure you can tell the difference between the smells when you fill-up at the gas station. 

Gas smell - take a look at the top of the fuel pump.  I had a leak on mine which I didn't even know was there except for the smell of gas and the fact that I just happened to notice gas vibrating around on top of it in the reflection from my chrome valve covers!  Since gas evaporates very quickly, especially when the motor is hot, the best thing to do to find it would be to stop, let the motor cool off, then crank it a few times and sniff around for where the smell is strongest.


If not gas, then a likely cause of exhaust smell would be an exhaust leak near the motor. 

Does the engine sound louder?

Take a look and listen underneath the RV with the motor running.  Run up the rpms a bit.  See if you can see or hear where the exhaust may have a hole or has separated (like at the Y pipe by the transmission or where the exhaust manifolds go into the the exhaust.

[dgapilot]

Gas smell - FIRE hazard!!!!
Exhaust smell -Carbon Monoxide hazard !!!!

In either case not good.
Do you have a CO detector in your coach? If not, invest in one. CO can kill you, it is cumulative and takes several days to clear from your system. You will find that you may have a headache and become lithargic.

[moonlitcoyote]

Thanks mark, I guess it didn't really smell like gas but the engine wasn't any louder either. Sometimes I thought it smelled like my sewer but I had just emptied the tanks. I'm just not sure what it smelled like. It seemed like a mixture of smells from sewer,exhaust and gas. . ..I'll see what I can figure out in the morning before we take off.

[tiinytina]

Only windows forward of the exhaust pipes should be open when driving. No rear windows... we usually have the roof vent in the bedroom open to pull air through and out. 

Tina

[cosmic]

could it be oil burning? when you develop a leak in the valve covers and it drips on the manifold it burns instantly and smells like exhaust but its oil smoke.
Take the cover off and start cold and let it worm up. fallow eyes and nose. 

here is a tip for checking exhaust leak. get some one with a rag to cover the tail pipe for a few seconds then off then on a few seconds. if there is a leak you will here it and find it.

[Oz]

Tina made an EXCELLENT point!  I recall, when I took my first RV out for the first time, I had left the windows open so there would be a lot of "good air" flowing through.  I smelled exhaust and realized that the draft behind the rig was pulling it back through the rear windows.  I closed them and just left the window in the kitchen and dinette open (which are right behind the cab area) and that solved the problem.

[moonlitcoyote]

I never open the rear windows because they are covered in plastic to try and keep some warmth in the back room. But I did find today that by keeping the cab windows closed I no longer had the problem. Maybe my sensitive nose just isnt used to smog and all the truck exhaust.  MJ