Rotten smell when accelerating hard 08 IS350

[Guest]

Every time I put my car in manual mode and do a pull from like second gear to fourth gear I get this rotten smell whenever I have the windows rolled down although when they rolled up I don’t smell anything as it doesn’t come through the cabin. any idea on what this could be? I also did they pull not being in manual mode and I didn’t really smell it as much either..

[dcfish]

Maybe your catalytic converter/s, Does it smell like sulfur/Rotten eggs ?

[Guest]

Yeah more of the sulfur side. But I don’t think it’s my catalytic converters because I don’t have any codes or anything. 

[dcfish]

You won't have codes until they fail or deteriorate, Been there, Done that. You can try cat cleaners.