This evening, when my wife was following me to drop her car off at the shop, she said she could smell a "sulfur" smell from my max when I would accelerate from a light. I have noticed a slight power loss from my car lately but took it for either the hot weather or bad gas. Now, I'm convinced there is something wrong or going to go wrong with the car. I checked my computer for any codes but none to find.
When we got home I had her rev the engine a few times and I smelled the exhaust from the pipe and noticed something funny. I do use 93 octane all the time from a gulf station near me. I used to have a few bolt-ons on the car, like a y, CAI, pulley but I returned the car to stock back in April.

Can anyone help and try to distinquish what may be wrong?

Thanks,
Tom

 

Sounds like your Catalytic converter is just about gone... the decrease in power usually results in the collapse/obstruction of the material inside it as it melts.

The cause of the failure is usually due to overheating by having an overly rich A/F mixture.

 

That does sound plausable but I had a RT cat on it for most of the life of the car. I just put back on the stock one a few months ago. It has less than 20k miles on it.
How can I check to see if there is a overly rich A/F mixture?

Thanks for help.

 

Aside from a exhaust gas analysis you could try A/F or EGT gauges but that would cost more...

Do you have engine mods? Other possible causes... bad sensors or leaky injectors...

Good luck.

 

If your cat is not working properly, it lets out sulfur dioxide, which smells nasty.

 

Also doesnt the A/C get a sulfur/rotten egg smell when something is wrong with it? I seem to remember hearing that from somewhere...

 

Now I get the rotten egg smell as well. I've always known that is a Cat Converter smell...however I've always been under the impression that when you smell it, that doesn't necessarily mean it's bad. My mom had a 91 Isuzu that you could smell the cat ALL the time (for the 10 years she owned the car)....She kept taking it in and everyone kept telling her that nothing was wrong with it just becuase it was smelling bad....

I wonder if the cat is covered by the Nissan Warranty?

In addition, with 60K miles on my car and no mods what are the changes of having an overly rich A/F mixture? I use the same gas all the time if that makes any difference.

 

Actually now that I think about it, when my cat was still on the car, I occasionally got "the smell". I still passed my local emissions test with flying colors.
If your car is running rich, the inside of your tailpipe will have a layer of black soot.

 

I used to have engine mods but took them all off back in April. I didn't smell anything before or after that. It wasnt until my wife mentioned something that sparked this worry. The tail pipe is "sooty" so maybe a high rich mixture is the cause?...
Anyway to change the mixture to flow better or if I reset the computer that may reset the mixture? Any help would be appreciated.

TIA

 

Could one of your o2 sensors be faulty, causing the computer to richen the a/f mixture? Try resetting the ECU, it definately cant hurt. Have you made none of your hoses have detached?

 

If your original cat's gone, and your car has less than 80k, federal law mandates that Nissan replace it. There's some time constraint, but I think it's like 10 years. Take it to the Nissan dealer that you trust and have them check it out.

If your cat's fine it'll cost you 30 bucks (that's what they quoted me) for their time, otherwise, it's free.

I would suggest checking the cat visually yourself or by a qualified mechanic to see if it's melted, just in case the dealership tells you otherwise.

-Mike

 

a slight rotten egg smell during WOT is normal, regardless if the car is modded or not. If it's excessive, then you have a problem.

 

My smell is not at WOT...It's when I shut my car off or when I'm idling...

 

if it's not the new perfurme you're trying, it's most likely the cat or bad gas..