Hi folks
Need help. My 2002 ls430 with 126k is giving a very bad sulfur or rotten smell only when accelerating hard. It also happens when there are 5 passengers and ac is in and getting on freeway. I have no codes and zero drivability issues.
I have changed both o2 upstream sensors from denso, Spark plugs, air filter. No oil leaks. I only put premium fuel from costco. Took it to muffler place guy said try change gasoline from costco to chevron or 76. However I'm having a hard time accepting that costco gasoline is the culprit since thousands of people fill up there including me when I had a 2007 lexus gs350 9 months ago and for a whole year I only filled up costco and never had this issue. If anyone had this issue and resolved it please share you experience. Thnx

 

What octane do you run?

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I always put the highest octane 91

 

Sounds like your catalytic converter is going out.

 

https://www.clublexus.com/forums/ls-...l#post10370558

 

Did you ever find a solution? My friend and I are having the same issue with our 2001 & 2004 LS430s!

 

https://www.hbautoandac.com/our-blog...ke-rotten-eggs

If it is only happening under heavy engine loads, then I would suspect the fuel pressure being too high but could also be either of the other 2 possibilities.