rotten egg smell....need solution

[Jesda]

This thread has gone right over my head.

My rotten egg smell is caused by bad cats or by bad fuel? And I can only get an OEM catalytic converter from a junked Q?

I assume that this is something any muffler shop can install... and if theres secondary CATs could the problem be related to a primary or tertiary CAT? All I understand from experience is that the exhaust goes through a catalytic converter and then out the rear. I had no idea there were multiple stages.

I want the rotten eggs to go away.

[elwesso]

Alright...

There are a first" (if thats what you want to call it) set of cats built in to the exhaust manifolds... They are mainly for startup emissions as once tehy get warm they arent supposed to do much...

Then there are a secondary set, probably a better name would be the PRIMARY set, the main cats that do most of the emissions crap... THey are right by the transmission...

The rotten egg smell can be caused by 3 things...

1. Cats not getting hot enough: This happens to me all the time, but not on my Q... On the grand prix if it doesnt warm up and you drive it hardish then it smells horrendous..... The cats have to get up to operating temp in order to do there thing...

2. Lack of cats or bad cats: If you dont have any then the sulfur in the exhaust doesnt get "filtered"...

3. Bad gas... Sulfur in the gas, and if its more concentrated in conjunction with no1 or no2 then thats the case...

I know Jesda your driving cycle is very short, so I bet if you made it longer the smell would go away.....

[Jesda]

Ahh, true. Because since work stopped and school started, I've only been driving 4 miles a day, and school is only .9 miles away.

[HeavyDuty]

Rob,

I suspect a combination of the above.

Header/exhaust leak.

High sulfur fuel

No cats (duh)

No EGR

My car without the cats, but with stock exhaust has a smell and more soot on the bumper than it did before. It's not horrible though, even standing behind the car.

My cats were plugged solid, that's why I gutted them, not the preferred method.

I think if you were to have a bung installed for your EGR (good luck, it needs to be stainless and won't be easy to reinvent the wheel there with your headers) install a good aftermarket cat like the RandomTechnology.com *metal* core cats, check for leaks (I know you have some), you'll be OK with your car again.

This stuff is frustrating, I know. Even when it's a per-application installation, this happens, needless to say when you're making the path instead of following it.

[par2za]

Here's my take on the problem the smell is caused by a rich fuel mixture. you did say the ck engine light came on so thats an indicator of a problem. now if your manifold is not sealed properly your probably having an air leak upstream from the o2 sensors and that will cause your sensor to indicate lean and your ecu will richen the air-fuel mixture. as for the EGR why did you diconnect it its the only thing to help with NOX build-up in your combustion chamber and is only operational during crusing speed at W.O.T (wide open throttle) the egr is inoperative due to the drop in vacuume. and especially since the engine has a 10.2-1 compression you cant just disconnect it. the Egr is designed to keep combutions temps under 1200 deg f. so disconnecting it your asking for trouble. And again as for your cats ck for any air leaks in your exuast above the O2 sensors or then you have injector or adjustments are off.

[par2za]

I have a few questions to this problem.1) What CATS did you install. 2 way 3 way... ect2) Did you use the same manifold or did you replace them as well.3) how did you disconnect your EGR4) and most important did this problem happend right after your Mods or everything was ok and one day this just happend. just want to know the whole story before we get into anything expensive and i dont like to just replace components.

[Q45tech]

Pretty important to read ALL previous POST and study the history [about a hundred posts] that he remove entire oem exhaust from engine block [new headers without egr or precats constructed], no primary cats and a loud custom exhaust.

Of course it will smell and kill all the folage and small animals and cause drivability problem, but he wanted that last 0.001 second of improvement.

Things one must learn to live with in search of improved performace.

[rsiwicki]

well.....just to give you all an update on my car since this thread was resurrected again.

I don't have any rotten egg smell anymore. I still don't have any CAT's on it and don't have the EGR hooked up. I rarely get a check engine light...only about 1 time every 2 weeks and goes away instantly after I shut off the car and start it up again. Now why I don't have the smell anymore is beyond me, but it stunk really bad for 3-4 weeks and then all of a sudden disappeared. I am working on getting some OEM things to stop the kiling of trees and the like, but for now the car seems to run fine and only time will tell if any serious damage is being done in the long run.

[Q45tech]

We pointed out the correlation between HIGH sulfur levels in gasoline and sulfur coming out the tail pipe!

[Q45tech]

We pointed out the correlation between HIGH sulfur levels in gasoline and sulfur coming out the tail pipe!

" I rarely get a check engine light...only about 1 time every 2 weeks and goes away instantly after I shut off the car and start it up again." ?

The hurricanes give them an excellant oppurtunity to dump the garbage again under cover of the emergency aftermath.

The usual method is just to combine the high sulfur with enough low sulfur to dilute it to reasonable levels.........sometimes they don't have enough or any low sulfur on hand..........normally the cats cover up this fact.........store enough sulfur for a tank or two till the clean gasoline washes it out SLOWLY...........no cats no staorage facility.............instant smells!

[rsiwicki]

I just got back from Mexico City and my car is covered in a thick mist of sea salt spray.....as I had to leave my car at the condo because I left the previous Friday before the hurricane came. I did not drive my car, but it turned over easily and seems to run fine as I was a little concerned since I live right on the beach and the car was left at the condo's parking garage on the bottom floor in an open area exposed to all the wind and elements, but no problems thus far.

I have been using the same gas station right next to the condo...Cheveron and all seems so far so good, but I plan by the end of this year to return the car to OEM specs....

[elwesso]

I just got back from Mexico City and my car is covered in a thick mist of sea salt spray.....as I had to leave my car at the condo because I left the previous Friday before the hurricane came. I did not drive my car, but it turned over easily and seems to run fine as I was a little concerned since I live right on the beach and the car was left at the condo's parking garage on the bottom floor in an open area exposed to all the wind and elements, but no problems thus far.

I have been using the same gas station right next to the condo...Cheveron and all seems so far so good, but I plan by the end of this year to return the car to OEM specs....

So that means your going to get rid of all the mods youve done???

[rsiwicki]

Don't really know yet on the mods whether to keep them or let them go....I will be buying another car (2 seater convert sporty car)within the next 6 months to replace this one...and either I will keep this one as a second car (when I need 4 seats) or sell it. For now...I am trying to reacquire certain parts just incase I want to return it to normal as these damn CAT's are not easy to find.

[elwesso]

Obviously mine might be avaialbe very soon.....