Guys my esxhuast smells like rotten eggs and i got a wierd smoke but i dont

[83countrysquire]

know where from i think its the car what could it mean if it is coming from the exhuast

[mrltd]

bad cats....cat could be over heating and melting stuff under the car. I clogged my stock ones and melted all the undercoating off a few cars...

[p71towny]

Yup, bad cats fo sho.

[87mefull]

Cataytics are bad, and you should replace the 02 sensors while your at it also.

I have a catted mustang h-pipe that I might be selling if you plan on upgrading to a larger exhaust.

[Tiggie]

Rotten Eggs = Sulfur, which could be coming from the type of gas you use.

[Mercracer]

Rotten Eggs = Sulfur, which could be coming from the type of gas you use.

Rotten Eggs = hydrogen sulfide. Yes, there is sulfur in fuel additives, but not enough to cause a smell with completely burned fuel although some brands may be more sensitive than others. An overly rich mixture can cause a buildup in your converter and give you the smell. An engine running extra lean can also cause a problem. When running lean, sulfur trioxide is produced, then when the motor goes rich when under load like going up a hill, the sulfur trioxide is converted to hydrogen sulfide. Some cars smell when warming up in cold weather but the smell goes away once the motor warms up. If the converter is building up, a good hot highway blast should take care of it. When a converter is failing and plugging, no amount of hot running will cure it.

[RugerP97DC]

Are you sure the other kinda cat didn't get stuck under there?

[83countrysquire]

guys its a brand new exhuast system built by midas

[grandpaslincoln]

The sulfer smell is normal.

[Mercracer]

guys its a brand new exhuast system built by midas

Just for fun, Midas put new cats on?

[83countrysquire]

yes they did b/c when i sent it there it had only headers on it and the bufflers and h pipe to build with

[Mercracer]

What does Midas say about your wierd smoke and smell?
If you bring your car to an emmissions testing station or to a shop that has a tail pipe sniffer, they can tell you if your fuel/air mixture is not right.

[Tiggie]

Midas will probably say that the new cats just need broken in or something like that. I've never heard of breaking in new cats, but anything is possible I guess.
Did the reattach the air tubes from the smog system? If they didn't, the reaction occuring in the converters might not be reacting to it's fullest extent due to the lack of oxygen. A sniffer test would tell you if the reaction wasn't going on to it's fullest.
The smell still exists after a long highway run? Try putting some fresh gas in of a good brand name, different from what you normally use.

[83countrysquire]

well they didnt hoook up those vaccum lines b/c they were rusted out but should i hook them up

[grandpaslincoln]

They aren't vacuum lines, teh air pump pumps fresh air into the cats via those tubes. I'd hook them back up, might as well use the new cats to their fullest.