Jaramars

Hey guys,

i have a 2015 IS 250 F sport. Today when I was driving on local suddenly I smell a bad smell like rotten egg or sulfur which is not from AC. Then I parked and found the same bad smell from the exhaust. I did fill up the 93 gas in the morning. I am a power train Calibration engineer so I assume it might be a bad CAT but from online info they said it might be due to bad gas... just want to check with you guys if anyone of you met the same situation. It is only as than 2 years old and I highly doubt the CAT could go really bad. Thanks guys!!

Boomin

Yea my wife's IS had the same issue and there's a huge thread about this. Hope it gets resolved.

Jaramars

the other thing that I notice is I am little bit lack of power. I did change my gas selection recently from BP 93 to speedway #93 which is closer to my work place. Wonder that might be reason, pretty sure Toyota's Cat is sensitive to fuel. But still cannot believe speedway made bad 93... So suspecting the CAT more, will try use up the current tank and switch back to BP before bring it to the dealer

Solara350

1st, because it's cheap gas
2nd, because its a small engine
3rd, every 4cyl or an old Engine will get that smell if you go WOT

You won't get that smell in 3.5L 3.7L 4.3L 5.0L

Sasnuke

The most common cause of the rotten egg smell is the fuel. Whatever it is about the fuel you recently switched to, the vehicle obviously doesn't like it.

Step 1. Run your current tank out as much as you feel comfortable...if you are ok with driving til the Low Fuel warning comes on, do so
Step 2. Switch back to your old gas station that you had no issues with.
Step 3. Repeat Step 1 approx. 2 to 3 times with your old gas station gas.
Step 4. Enjoy...your rotten egg smell is gone now

On a 2 year old Lexus, I doubt the Cat's are any cause for concern.