jpv7774

04 LS430 with 135k on it......just purchased...so new to me. She rides smooth as silk but I have noticed after I goose it a bit a I smell a little Cat smell......This has happened a couple of times so I cant keep blaming it on other cars. My wife blames the smell on me!!!! I did a search on this site and read a lot of dif scenarios...only a couple on LS430s..........keep in mind...my car is a garage queen. I dont drive it very much. It doesnt roll down the road smelling like rotten eggs.....I can only get her to stink after a good goosing. Some posts say to switch gas stations.....or that the stink means the cat is doing its job.......

Refreshing an old topic......maybe I can get some new answers. I was hoping if it is a cat going bad...maybe I could correct the issue before the cats crap out.

XJSFan

Try a few tanks of premium 93 octane gas and a bottle of BG44K... This has helped a few people I know with other cars that had the same issue.

StanVanDam

All makes and models of cars are susceptible to this. The general Lexus all-models TSB is EG001-03, title SULFUR ODOR FROM EXHAUST, published Feb.24, 2003. The only corrective procedure is to try a different source of fuel, as the source of the smell is from the fuel itself.

Replacing O2 sensors or catalytic converters will NOT reduce the odor.

I personally recommend using a Top Tier certified gas, of at least the minimum recommended octane specified for your car. See http://www.toptiergas.com/retailers.html for retailers in your area.

jpv7774

The car is new to me with 135K miles on it. Given some of the threads I have read and your replies....I will assume previous owner used mid grade or regular octane.........I will only run the good stuff so maybe it will clear up after a few tanks. Its not bad....But have noticed a few times for sure

RA40

iTrader: (6)

Good gas and a drive at highway speeds to get the cats at operating temperature. If the car is only seeing local short runs less than 10 minutes that doesn't help.

adilyaqoob

The smell is due to the converters, not the fuel. I have a 2001 LS430 and I had the same issue. The day I changed the converters, the smell was gone.
I had the exact same issue, push the car for a few minutes and the sulphur like smell starts coming which takes a while to go.

Boomer01

I have the same issue. I just live with it and try to not take it over 3000 rpm.

bmore430

I noticed the same in my 2005. It will stink whenever the car is driven hard for a few minutes then disappear. I have around 77k. I think this is a classic sign of cats getting age and mileage. I plan to replace the cats when I do a full exhaust upgrade to cure this.

XJSFan

Every time I am on a onramp to a freeway behind a Toyota or Lexus, it always smells like eggs/burning...

jayclapp

I don't understand this. I purchased a 1992 SC400 new in Dec 1991 and drove it until it was totaled in a wreck early this year. In the Phoenix area we were requird to have a yearly emission test. During the 23 years of driving the car in this area and accumulating 205,000 miles it never even came close to meeting the maximum emission levels. The muffler and cat were never changed or off the car for any reason. The initial new car emission level was a mere 1/10 of the max!

So what's going wrong with the new cars? Cats and mufflers should last just as long as my old 1991 manufactured ones, I would think.

jpv7774

Adily..........

How much did it cost for u to replace both of your cats?

UGKkllr

has nothing to do with fuel . I have this rotten odor every time i rev over 3500 RPM's or so and i have tried all kinds of gas . you would think a car that cost 75 grand new would not have this problem

Slvr surfr

iTrader: (1)

Well i can say this. After getting my car back from having the B1S1 02 sensor replaced due to the wires being broken, i did notice a cleaner, almost nonexistent exhaust smell. Before i would get the rotten egg smell when push slightly harder than normal. I guess because it was running rich due to that sensor not giving up pre-cat data. Now the smell is almost undetectable. I think it has to do with a combination of things such as worn sensors, cats, fuel. Just my two cents on what cleared up mine.

BradTank

When I changed out my spark plugs, I noticed a MUCH less smelly exhaust. I'll still get a faint whiff of it every once in a while, but it used to stink up the whole garage when I pulled in. I had also changed out my upstream O2 sensors a few months before.

I don't want to say definitely that stopped the smell and everyone rush out to change their spark plugs thinking it will cure it, it could have been another random factor. But I still use the same gas from Coscto I did before, so that wasn't the issue.

I was about ready to put new cats on there it was so bad before. It was like an open sewer, even my kid was commenting how bad my car was stinking.

My guess? Maybe the older plugs weren't burning up all the fuel and a richer exhaust was making the cats stink?

Slvr surfr

iTrader: (1)

I definitely think it has something to do with what the fuel system is putting out. Maybe it was a combination of things in your car that made a difference on how it smelled. My exhaust manifold was cracked when i had that bad upstream sensor so you can imagine the smell in side my car when i had the windows down. Not only that, the possible danger it causes breathing that stuff in.