rotten egg/fart smell from my 02?

[psychotic]

hey guys, my 2002 w/ the 4.6 v8 has a lil problem that i'm hoping one of you might know the solution to. If I keep my engine in the higher rpms for too long at highway speeds, when i let off it smells like someone ripped ass or threw a rotten egg at me.
Some examples when it happens:
flooring it coming onto an on-ramp at about 20, and continuing to keep it floored until about 85,
or flooring it at around 65 and going up to 90 or 95.
then it will smell like rotten egg for 1-3 min.

I think it might have to do with an emmisions sensor or valve not working right? anyone know what this means for sure?
thanks for any help!

 

[410Fortune]

Its coming from the catalytic converter(s). Most likely dumping too much fuel from the engine, does the check engine light come on?

How many miles on the truck?

Quit driving like a maniac!!! hahaha

 

[MONMIX]

Your driving sounds a wee bit agressive, but either way, an 02 should not have these symptoms. 410 hit the nail on the head. Rotten egg smell is almost always cat related.
I will assume you are still under warrenty, get the boys at Ford to look at on their dime.

 

[psychotic]

roger that.
i don't drive like that ALLL the time. but sometimes you gotta have fun. let the horses run. just i don't like it when they fart.
i'll tell ford to fix it along with the tranny whistle.

 

[Glacier991]

The following explanation is not mine, but out of my archives - on the WHY of the rotten egg smell:

"The sulphur smell from the exhaust, is actually caused by running the engine/cat convertor slightly lean for long periods and then running under a rich condition (ie going up a hill under heavy load) This is when the sulphur smell (rotten egg) is produced.

Under relatively lean conditions, the sulphur found in gasoline is converted to sulphur trioxide, then during the rich running condition the sulfur trioxide is converted into hydrogen sulphide (rotten egg smell) within the catalytic converter."

So, you can try different brands of gas, or check and see if your Forward O2 sensor is lazy. If you are not getting a MIL (CEL) light, it's probably only lazy (e.g not switching fast enough.) You couldhook up a scanner and count the crossovers - should be 8 per minute or higher. I'm guessing gas and maybe the lazy front O2 sensor.


Happy, and less smelly, Exploring

 

[V8BoatBuilder]

...it smells like someone ripped ass....

We have such classy members on here

 

[Rodeo Joe]

What brand of gas are you using? I've had the same experiences in the past running Shell. Something else to think about.

Joe

 

[85Dave]

There's nothing wrong with your engine. Sulfur in gasoline plates out on the surface of the cat converter during normal operation. When you accelerate briskly, the heat and addition fuel cause the sulfur to "burn off". The sulfur comes off as hydrogen sulfide, which is what the "rotten egg" odor is. Premium gas is normally low in sulfur. In about another year, all gasoline will be low in sulfur, per EPA rules.