[SRT6INTREPID]

I like to horse around with the car a little... er a lot. Something I don't think I'll grow out of.

I've noticed recently if I dump the peddle to either roast tires or accelerate quickly, the vehicle emits a HORRIBLE odor. You cannot smell it inside the car at any time, seems to strictly be coming from the exhaust and effects the area I was in during the acceleration.

I've had comments and noticed the smell myself when I pulled into a gas station and the car ran as I filled the gas (cold morning, gas station across the road :P).

Was suggested it could be dying cat converters, or charcoal canisters?

[BatCaveTrep]

You may need to be more descriptive on the smell than just "horrible". Does it smell like a skunk, eggs, tulips, etc? Please do not put gas in the car while the car is running and there are other people at the pumps. You can put your own self in danger, but hopefully not others. I think that is fairly self-explanatory.

[95intrepid99kid]

Great, now I need to ask a stupid question: Why? If the engine is going to toss something back up the line going down the road, it will do the same thing (on a smaller scale) as at a gas station. While its still a good idea to have the ignition off entirely, this could happen w/out warning anyways (esp. from a neglected vehicle)

[SRT6INTREPID]

The smell is hard to describe. I'd say anywhere along the lines of rotten eggs and sewage.

[Crash Override]

Sulphur dioxide (rotten egg ) is usually a sign of issues with the catalytic converter

[luckkky13]

I agree !!

[MasterTech]

You get the same smell from a vehicle that is wide open throttle or running rich if the sulphur content in the gasonline is high. If it is the cat not being able to store oxygen the computer will set a code, provided you don't already have a code preventing it from running the monitor. It could just be the fuel and cold temperatures which give you a very rich mixture.

[DrDodge]

the biggest reason to shut the car down while refueling, is so simple, when running the fuel system is under a small amount of pressure,, ( the reason we have Evap codes) create a leak by say removing the cap and tossing 10 bucks of 87 in the tank,, well,, now you get the idea..

[DrDodge]

we have a winner,, dumping raw fuel will give the rotten egg oder,,

[MasterTech]

You could saturate the canister if the system is running canister purge, or you overfill the tank. Any electrical spark from the pump motor can be dangerous when air is introduced to a tank normally full of vapors. The pump is cooled by the fuel, if you introduce cold fuel to hot motor windings, you could have pump failure. So leaving the car running is dangerous and unwise. À saturated canister could be the cause if your car is running rich giving you that rottin egg smell.

[95intrepid99kid]

Could be a furry critter up the exhaust has begun to decay or something. happened to me and required full pressure on the exhaust system (I don't remember how they did it, but it wasn't flooring it, and you've already tried that apparently ) Right?

[peva]

I disagree. Not only is the fuel pump cooled by the fuel, all of the parts in the pump and the motor (armature/commutator, brushes, pumping parts (gerotor, turbine, or rollervane as the case may be), bearings (usualy as simple plastic bushings)) actually live in the fuel. Yes - believe it or not, the brushes and commutator are in fuel while it is running. I don't know how the only missing ingredient (air/oxygen) could get into it. Even if you run it out of fuel - the pumping section is below the commutation section where the arcing and sparking occur, so there will always be a column of fuel above the pumping section surrounding the motor parts (brushes, commuator, etc.) - no air/free oxygen.

No way the sparks in the the motor can reach the vapors in the tank since the brushes and commutator are totally enclosed in the sealed pump assembly and further isolated by being totally submerged in liquid fuel.

What I want to know is: Who was the first engineer to propose routinely running fuel thru a d.c. brush motor? I wonder if that had not been tried and proven years ago if corporate lawyers today would allow any client to be the first to do that in their vehicles. But as far as I know, no car has ever exploded due to this arrangement.

[MasterTech]

I did say that the pump was cooled by fuel. I know that on a return style system you can have pump failure when cold fuel hits a hot pump, and I know liquids and solids will not burn just vapors. Exploding is for the movies, but you don't want to be holding down the handle on a fuel pump when a fire happens. I agree that the system is designed so that it does not cause fire, but things happen and air can be sucked into the tank with the venturi effect that we now use to prevent vapors from escaping into the atmosphere. Mix vapors with oxygen and then all you need is a spark, the spark doesn't have to be the brushes contacting the commutator, I should have said assembly not motor, it could be a loose connection on the pump or pump assembly. More than likely it would come from the current flowing threw the fuel level sending unit contacts. It is possible, and thats why you use nitrogen and not oxygen to do evap tests. We learned a lot of lessons from a little car named pinto.

[SRT6INTREPID]

I noticed the inside of my exhaust around the tips is pretty black, perhaps maybe it is running rich, but it may very well also be the cat's on their way out. I was considering cutting them out and removing them all together.

[peva]

I wasn't disputing that - I should have worded it differently - something like "You said that the fuel cools the pump, and that is true. But all of the parts in the pump and the motor...actually live in (are wet with and totally surrounded by) the fuel."

Though ours doesn't have a return loop all the way from the fuel rail, it is return in that the pressure regulator located in the fuel pump assembly dumps the excess immediately back into the tank - a "loop" of less than a foot. Not sure how our pump can get hot enough that more fuel flowing thru it could cause a failure. Trying to think of how that would come about, but I don't see it. The pump would only be generating heat when it's pumping, and whenever it's pumping, fuel is flowing thru it, cooling it (yes - as you said).

What about when the pump is running with the tank empty - you do have the column of fuel still in it, but it's not flowing, so the pump would heat up - right? No - because the PCM will disable the pump from running more than a second or two at a time when you first turn the key on and, until it detects that the engine is actually running, will keep the pump from running any further - hence no heat buildup. I just don't see any scenario of cold fuel hitting a hot pump and causing any type of failure on our cars.

I'll buy that.

Not sure there's enough current to cause any spark there, but for sake of argument, OK. Probably more chance of static from your clothes setting it off.

Are you saying that they used to use oxygen for evap tests? Whoah! That is crazy.