I just wanted to update some. I had been using Hess gas mainly since I bought my car because it was always the cheapest using 93 octane.
I have been trying different gas stations brands and have tried Shell and Mobile so far. Doing at least 4-5 tank fulls of each different gas brands. Shell dramatically reduced "the smell" in frequincy and amount of stank. Mobile reduced the frequincy of smell but when it did smell it was alot worse of stink. I just started yesterday trying Sunoco. We will so how that works and I will also try Lukeoil and Texaco and a couple other brands around here and I will keep the board informed.

 

My RX330 gives off this odor under heavy load (high throttle), especially when going uphill. I agree with some of the above posters--this is an issue with the catalytic converter. I want to try switching over to an aftermarket, but while I'm doing that, I'd have to get a welding and cutting job done first. Is there anybody in ClubLexus who any of you know have replaced/upgraded his/her catalytic converter(s)?

 

they have a TSB out for the cats on the 2002-2003 ES, which applies to my 03...i get a wicked whiff of sulfer if i accelerate heavily or go up a steep incline...the TSB covers a cat replacement under the 8/80k warrenty on emissions equipment...maybe something like this applies to your lexus? I know from being a tech that this is very very common on toyotas, esp V6, I6 and V8 powered models.

im having mine looked at at sheehy lexus of annapolis free of charge, and they will replace the cat if necessary

 

if unburned gas gets into the cats it will make this smell and damage the cats. so I dont think its normal. My IS doesnt do this.

 

ok i need an update on this....someone replace their cat and let me know whats up..i wnt to lexus dealer nd they told me tht replacing a cat wont do the trick...? the dude showed me print outs of the tsb's and that they had replaced cats bfore but tdidnt work....i iono mayb he tryin to hustle me..hence the name (stealership) but it only happens to me when i WOT and come to a complete stop really fast like at a red light......ITS ANNOYING thats the only thing ill change on my car lol I NEED UPDATES someone shed some light on this

 

This is NOT only for Lexus I've experienced it in my Toyota Sienna '03 and Highlander '08 and now my IS F '08. It gets annoying and irritating but best thing to do when sulfur burns just roll down your window unless you like sniffing it and having your cabin smell like it.

 

Has anyone notice a moldy or musky smell coming from their vents when they first start the car and the FAN ONLY with vent open and/or close or driving with vents open?

 

that is a whole different smell and covered endlessly in many threads and many makes of cars. It results from mold growing on the fins of the evaporator in the air box. Many home cures on the web. You can also take the car in to your dealership and they can "mist" the entire car. Costs about $150 but will do the trick. You can start by changing you cabin filter and searching this site for AC odors.

steviej

 

Thanks Steviej for directing me on where to look it up. I'm just surprised at how fast the mold growing inside the car, I just got my car and been owning it for 3-4 weeks and a little over 1k miles.

 

The "Cats" that are put on nearly all American modern cars are ceramic.

So change to a "Metal" cat.

When the cats are not up to the required temp to effectively clean the gases. it clogs up the honeycomb of the cats.
When the cats are at operating or above temps they put out a "stinky" smell. It is the additives that is put into the fuels are being burnt off the honeycomb.

Reset the computer
check the o2 sensor/s
replace o2 sensor/s or replace cats if needed (or what ever is cheaper)

 

oh my god you are all crazy... there is nothing wrong with any of your catalytic converters unless you get that smell all the time... (and then its probably a fuel system problem, not a catalytic converter problem)

that smell is a byproduct of the sulfur that is in the fuel (you can try changing brands, but all have some sulfur content), and the fact that the sulfur is not being burnt completely...

give you a little knowledge of how a modern ecu in a car works... 99% of your driving is done in whats called "closed loop" mode... the ecu looks at airflow from the mass air sensor, estimates the engines fuel requirements by plotting airflow, rpm and engine load on a preset fuel map and opens the injectors for that set amount of time... it then looks at the data from the oxygen sensors to see how completely burnt the fuel was - the more burnt it was, the leaner the mix, the less burnt, the richer the mix... it measures the oxygen content in the exhaust to do this, and it is looking for stoichiometric, which is 14.7 parts air to 1 part fuel ratio... anything below this is rich, anything above is lean - lean is good for fuel mileage, but not so good for keeping an engine healthy... once it sees how good the map was at estimating fuel requirements, then it modifies it... typically it will shoot rich, see if it was rich, then it will shoot a little leaner, see how well it does, then rich, then lean - its almost impossible to get it perfect every time, so it bounces from rich to lean pretty consistently... this is why an air/fuel ratio gauge bounces back and forth while at idle or cruise...

now, that other 1% of driving is done in whats called "open loop" mode... this is reserved for high amounts of throttle or wide open throttle... here, the computer abandons the oxygen sensor readings and only looks at the airflow and its preset map... because oxygen sensors are only accurate at stoichiometric (unless you have a wideband, which most cars do not come with from the factory), the programmers of the ecu decided that to save the health of the engine, they would shoot for somewhere between 10:1 and 12.5:1 for high loads on the engine... this is a safety factor - the additional fuel keeps the engine cooler and prevents knock... ok, so, open loop, no feedback from the oxygen sensors because we are operating outside of their accuracy range... also, a byproduct of this is that unburnt fuel makes it through the engine, sometimes to be somewhat reburnt in the catalytic converter making it get real hot... so, real hot catalytic converter plus sulfur in the unburnt fuel equals bad smelling exhaust, rotten eggs, to be specific...

it is not bad (unless it smells all the time) and it is not going to hurt anything - high temperatures can actually help keep a catalytic converter free from contaminants...

 

the additional fuel keeps the engine cooler and prevents knock

wrong

knock happens when fuel ignites irregularly and prematurely, causing erratic pressure differentials within the combustion chamber. Small explosions literally result potentially damaging the pistons and other parts of the engine due to octane being to low for the operating conditions its under

 

no, I'm right... I know exactly what knock is, I was just trying not to go into too much detail as that is not what this thread is about...

additional fuel lowers exhaust gas temperatures across the board, therefore the engine runs cooler...

also, additional fuel prevents knock - a lean condition makes an engine knock bad - you can combat that, or even combat having too little octane by adding additional fuel...

so, my original statement stands, you prevent knock and keep the engine cooler by adding more fuel to the mix... this is tuning knowledge 101...

You stated what knock was, but never what caused it other than octane... another very common cause of knock is too much timing advance...

One thing I did have to rethink myself on was if you thought I implied that a cooler engine prevents knock as well... thought about it for a second, and guess what, that is correct as well... again, pre-ignition is caused by all kinds of things - and one of them is a combustion cylinder that is running too hot and causes the fuel to pre-ignite... again, octane can solve this problem, but so can additional fuel to cool things down a bit...

now, can we get back to the rotten egg smell...

 

one more edit - for the record on my old turbocharged talon, I could get by running in excess of 20 psi on a pretty big turbo (20g) and still on 93 octane fuel, just by adding additional fuel to compensate for the lack of octane... when I went to MS105, I could take the same boost pressure and lower my fuel requirements about 15% under load, as the added resistance to knock was given by the change in octane, not the additional fuel...

 

I think you guys might all be wrong. In my experience of working with many different cars (literally almost every car you can think of) The rotten egg smell usually only happens for one reason and that is when there are excessive voltages or there is an electrical issue regarding either the alternator or the battery. And if the smell is the same one I'm thinking about it's the rotten egg smell you get for example from a bad battery or shorted battery or an ill-maintained battery/terminals. I smell it often too when I Floor it in my Lexus. But I have smelt it in many different vehicles. I think when the RPMs are shooting way up the alternator is somehow over powering the battery and creating heat/pressure in the battery. And this is something I have smelled in a lot of cars. If you don't believe me . Drive hard, Pull over, open hood. And smell the battery area. Chances are the terminals by the battery will have residue or battery acid. and it might be boiling. I have no service lights and no cat issues at 140k miles