Rotten Eggs smell from 92 Toyota Pickup Exhaust

[JAYCEE]

Lately I've been getting a rotten eggs smell from my exhaust on a 92 Toyota Pickup with 220k miles 3VZE. All emissions and exhaust stuff is original. I run Mobil 1 10-40 or 10-30 and I use FP3000 about every fill up.

I do not get a CEL, so should I try replacing the O2 sensors first? What are the odds I need a new cat?

 

[tinmanSC]

Have you been using the same gas station? Sometimes this can be caused by poor gasoline. This can also be caused by inefficient combustion (rarer, but happens on some cars older than 1996). Try changing gasoline stations for a while, if that doesn't resolve the issue, try a tune up. If the issue remains.. well... might be time for a new catalytic converter but I'd do this last.

 

[dtt004]

Hi.

It is the catalytic converter. Your check engine light will come on soon, indicating a need to change the catalytic converter.

You should not change the oxygen sensors, because that will no nothing about the smell. The smell is due to the inability of the catalyst to perform the reaction required to convert poisonous and harmful exhaust gases into less harmful gases. The oxygen sensor is an analytical system used for emissions control purposes; it doesn't take the place of the catalytic converter.

I do not believe it is due to incomplete/inefficient combustion. If it was, the exhaust would smell like fuel, not rotten eggs.

Gas from any station is still gas; they only differ in the additives inside. These changes do not cause a rotten egg smell to occur.

I think you need to change the catalytic converter soon.

 

[tinmanSC]

Originally Posted By: dtt004

Gas from any station is still gas; they only differ in the additives inside. These changes do not cause a rotten egg smell to occur.


Yes it does, and it has happened to me. I don't know where the gas came from, it was from a local station. I'd been using Shell and BP for 4 years, then filled up a some local station far from home and had a problem with sulfur odor, this issue with resolved on my next fillup. The gas can be a problem, but I agree that the converter is more likely.

 

[Volvo_ST1]

Originally Posted By: JAYCEE
Lately I've been getting a rotten eggs smell from my exhaust on a 92 Toyota Pickup with 220k miles 3VZE. All emissions and exhaust stuff is original. I run Mobil 1 10-40 or 10-30 and I use FP3000 about every fill up.

I do not get a CEL, so should I try replacing the O2 sensors first? What are the odds I need a new cat?


You probably filled up with poor quality gasoline that has a high sulfur content. The poor gas quality has been problematic for Euro car manufacturers for a long time, and Japanese car may be affected also.

Anybody remember BMW and NIKASIL? The high sulfur in US gas destroyed the NIKASIL cylinder liners in a number of BMW engines.

Drive the tank empty and gas up elsewhere. If that doesn't help there may something wrong with the cat.

 

[JAYCEE]

I almost always use Valero gas which is known for refining the high sulfur oil that others won't touch. Sour gas? Sour oil?

I'll try a couple of tanks of Shell or Exxon to see if that helps any.

I was hoping to get a few more miles out of this truck, I'm not sure I want the expense of replacing the cat. I wanted to hold out for the plug in Prius to be widely available before I bought anything new. I guess I may be in the market for something new sooner than I planned.

 

[JAYCEE]

For some reason, I thought new cats were about $2000. Looks like they can be had online for under $200. There's a muffler shop near me that I can get to replace it.

Should be no big deal.

 

[JHZR2]

Its the gasoline. Ive gotten this on new cars, brand new cars in fact, as the converter heated up and burned off the adsorbed sulfur.

New cats are around $1600. Maybe more given metals prices. The $200 versions have so little active metal that they barely do better than a failing cat. Been there, learned that. Someplace on here I have my experiences and readings from my 91 318i with old bad cat, $200 special, and then OE replacement.

 

[carlprop]

Found the thread!

http://www.bobistheoilguy.com/forums/ubb...true#Post923100

 

[Jakegday]

if it is gas, i was filling up with "bad" gas 2 times a week for a couple months straight, and the day i cut my cat out, all the gas stations somehow switched back to "good" gas..

in my part of the country, for a shop to put a new cat on either of my cars, would be $4-500.

 

[antonmnster]

OK, a sulfur smell is a symptom of another problem.

Your cats produce this smell when they're overloaded with a rich fuel mixture and overheating. People are saying the cats are bad... not quite. They will BECOME bad if you keep driving.

Odds are high that you have a lazy o2 sensor, an intake leak, or some other tune problem that's causing your engine to run rich. Treat the cause, not the symptom!

 

[Rix]

Originally Posted By: dtt004
Hi.

It is the catalytic converter. Your check engine light will come on soon, indicating a need to change the catalytic converter.

You should not change the oxygen sensors, because that will no nothing about the smell. The smell is due to the inability of the catalyst to perform the reaction required to convert poisonous and harmful exhaust gases into less harmful gases. The oxygen sensor is an analytical system used for emissions control purposes; it doesn't take the place of the catalytic converter.

I do not believe it is due to incomplete/inefficient combustion. If it was, the exhaust would smell like fuel, not rotten eggs.

Gas from any station is still gas; they only differ in the additives inside. These changes do not cause a rotten egg smell to occur.

I think you need to change the catalytic converter soon.


NO.
There are brand new cars suffering from fartsmell-itis.
There are some fuels that have a higher sulpher content than others.
The 92 truck is not like the newer cars where you can program the ecu to change fuel trims and burn to help decrease smell, but you can check and see if certain things are ok, primarily o2 sensors (make sure they aren't getting lazy), plugs for wear, and you can check the voltage feedback (fuel trim) to see if it's time for an adjustment.

Trying a different fuel station for a while (several tanks) is the better bet.

 

[friendly_jacek]

The sulfur smell is H2S. In order to produce H2S one has to have sulfur in gas that is combusted to SO2 (that is not very smelly), SO2 is oxidized in a cat to SO3 during lean conditions and accumulates there (solid as opposed to gaseos SO2), and then one has to have periods of rich mixture (usually by flooring the gas pedal) when SO3 is reduced to H2S that is very stinky.

The easiest way to deal with the smell is using low-sulfur gas. One can also look into emission components to explain why mixture would be lean and rich at different times.

And yes, it happens in new cars, especially Toyotas. I had that a lot in my Corolla, but it went away when I switched to better gas like BP or Exxon. Toyota also offered TSB with ECU reprogram and improved cats.