Fumes In Cabin

[V1]

What is the best way to ensure that no harmful fumes are present in the passenger cabin?

I've been dealing with a fuel odor in my engine bay, but I want to be sure that none of it gets into the car while I'm driving. The outside air vent stays closed. Is that usually enough to keep any bad fumes out? There are no noticeable odors unless I open the vent, and the car is parked at idle.

 

[MrCritical]

What make and model car? On some models, if you keep pumping fuel after the automatic shutuff, there's a line going from the fuel tank to a charcoal canister under the hood. The canister will fill with fuel and hence your fuel smell. Also check the fuel lines, especially at the connectors.

 

[Merkava_4]

Holy Smokes! You still haven't found that fuel leak yet?!? I remember reading about this case like two months ago. The fire wall is not sealed off from the passenger compartment; closing the vents off isn't going to stop all of the fumes.

 

[01rangerxl]

Honestly, you really need to find the source of the smell and fix the problem. If you can smell gas, you are almost certainly being exposed to fumes.

Be sure that you do not overfill the gas tank. That will cause fuel to back up into the charcoal canister.

Even if the car is out of the powertrain warranty, it may still be under an emissions warranty. It is probably worth your while to find out if this is a problem with an emissions control before the warranty runs out.

 

[V1]

Guys, believe me, I'm trying to figure this out as best I can. So thank you for all your help. I very much appreciate it.

Mazda incorrectly diagnosed the problem once already. So right now I neither trust them with my car nor my wallet. Besides, I do believe that I will figure this out soon enough. At least my driving time is minimal since I'm usually out of town.

I honestly smell nothing in the car while I'm driving. My biggest fear is carbon monoxide. I don't think my exhaust leaks, but how can I be sure? Are gasoline fumes harmful even if undetectable?

 

[Quest]

OK, here's the truth:

-All vehicle cabins are not air-tight. You will suffocate if you happen to have one (LOL!)

-unless you are operating your vehicle in a confined environment with no air circulation and such (inside an indoor garage w gate shut), otherwise, there shouldn't be any concerns RE: CO getting into your cabin (unless you have a seriously cracked exhaust or manifold).

Lastly, are you one of those guys who likes to fill your gas tank all the way to the brim after the nozzle shuts off? If you do, that is the cause of your fuel problem. Modern emission-controlled vehicles do not permit overfilling of gas tank and if you intentionally do so, you'll end up either smelling gas in your cabin (quite common), daming the EVAP unit (causing you mega $$$), charcoal canister, or a combination of both.

Q.

p.s. I seem to recall that there's a battery operated Co detector available somewhere.

 

[V1]

Quest, I hope you're wrong.

Ok, suppose the EVAP system is indeed damaged. Whereabouts would the fumes emanate from then? In the vicinity of the cannister, I would think. Except in my case the fumes are from right atop the engine.

Mazda advised me to replace the intake manifold gaskets. No fix. So my best guess right now is that either an injector or the intake manifold itself is leaking.

 

[GMBoy]

Just for kicks - why not just fill your tank to like 3/4 full for the next 3-4 tanks to see if that allows the EVAP system to purge itself?? Just an idea and wouldn't cost ya anything. If the smell goes away - you can narrow down your list of culprits.

 

[wiswind]

If this is for your 2004 Mazda, you will have a Check Engine Light (CEL) if your evap system is not working.....as that is part of the required OBDII monitored items.

You could have a pressure check done on your fuel system.

A intake manifold gasket does not seem to make sense for a fuel leak.....if it were leaking such that you would smell gasoline, you would have a CEL for lean codes from the oxygen sensors.
The intake manifold is at a vaccum most of the time that your vehicle is running (except when you have turbo boost, if you have a turbo).

A leaking fuel injector is possible.

Some charcoal canisters are located underneath the vehcile, not in the engine compartment.

What I would recommend is a goggle or yahoo search on '2004 Mazda 6 fuel' and see what other's with your same vehicle may have found.
Each vehicle has it's own common failures.
As you mention having it to a dealership, they should have run your VIN for any recalls or TSB's that would help them out.

 

[mechtech2]

Using recirculate is your best bet. I'd crack a window anyway, to get a bit fresh air .
As you know, gas leaks are very important.

 

[MrCritical]

The only parts covered under the emissions warranty are the catalytic converter and the PCM/ECM.