Hi Club Lexus,

I did the "F Sport" intake mod aka drilled two 1.25" holes on the bottom intake box. When I turned my car on it had a check engine light, VSC light and traction control light came on. I cleared the codes using an OBD scanner and they never came back on. A few weeks later I noticed every time I floored the car it made a rotten egg smell. What could this smell be coming from? Are the holes in the intake box causing the MAF sensor to make the car run more rich?

 

Mine has done that for years. I always thought it was just burning off the carbon. Never had any issues other than the bad smell. Never had an issue with carbon build up either l.

 

The sulfur smell is today's gas in combination with the catalytic converter. Not much you can do about it.
There was a post somewhere about some vents in the trunk that get old and don't close properly, they may need to be looked at. Some say its difficult to swap and others say its not.
Then again, maybe i'm wrong all together...

 

or do a search

https://www.clublexus.com/forums/is-...amps-fail.html

 

This, unless you invest in new cats in hopes that it may help the issue.

 

Depending where you live, and drive. The holes will alow more dust to be sucked into the air box. Hence the filter will get dirtier quicker, and possibly clog.

I had this happen to me on a few occasions got codes for rich bank 1.

Since my morning commute involves me to drive on a dusty strech of road. All the cars in front of are kicking up dust.

I found my AEM clogging up. Even its harder to tell with the OEM filter. I had it happen as well too on it.

So now I find myself washing out the AEM out every 2 weeks just to be safe. I keep an extra OEM filter while I let the AEM dry.

 

Thanks for all of the input guys. I think I'm just going to deal with it. I can only smell the sulfur smell when my windows are down.

 

No, wait! Below is part of a thread on a Maxima message board indicating that your MAF sensor may need attention.

I have a 2K se which had been experiencing problems

1) When i punched it on the highway I too would get the sulfur stink.

2) On cold morning startups it would buck in 1st and 2nd. After about 2-3 blocks all was fine.

I figured I would change the MAF being it's so cheap.......Glad I did!!!!!
Both above problems are gone!

 

Other things that I' seeing in other car forums that could cause the rotten egg smell: bad fuel pressure regulator, dirty fuel filter and, get this, very old transmission fluid.

 

Thanks brother! I get bucks in 1st and 2nd gear too! I'm going to change out my MAF sensor and see what happens. If not, I will start looking into the other things you suggested. Thank you for your input!

 

You could simply try to clean the MAF sensor wires with a spray MAF cleaner that you can get from any auto parts store.

 

I watched this video on how to clean the MAF sensor and it said not to use with most Lexus vehicles.

 

I have an 08 IS250 with about 155k KM (96k miles) and had the same problem with a horrible rotten egg smell anytime the car was above 4-5000 RPM for longer than a few seconds. Smell was unbearable at WOT. Lived with it for about a year being unsure on how to fix it.

I recently had the engine walnut blasted to remove any carbon buildup (preventative measure, didn't have any carbon buildup symptoms) and have not had the smell ever since, I haven't done anything to the exhaust/cat system. I even intentionally kept it in the high rev range for a while to test if the smell would come back at some point but it did not. This leads me to believe that carbon buildup might be related to the smell. Not a mechanic so I'm not sure but carbon cleaning the intakes got rid of the smell for me!

TL;DR: Carbon cleaning got rid of the smell for me

 

May I know what it means? - it doesnt make any sense. This slang is so hard to understand for ppl from europe (at least for me).

 

Walnut blasting is a way to clean the intake valves on a direct-injection engine like the IS250.

Not Lexus but a direct injection engine