Bad Exhaust Smell!

[ProjectIS]

Somethin ain't right!! Yeh, I agree with the fact that the cats can be the issue, but how about Ilv's brand new Rx or all y'all with relatively new rides. I've got 11k on my car and I have never smelt it even under hard driving.

What fuel are y'all using??? There needs to be a common link!

[ilv1004s]

spoke to the service guys they said if u got the a/c on it wont smell

but man..

a/c + trash = too much fuel

[ProjectIS]

spoke to the service guys they said if u got the a/c on it wont smell

but man..

a/c + trash = too much fuel

Trash or thrash?!?!?!? :D

Seriously though, what roll the A/C play in this??? I wonder sometimes about the service dudes!!

[dazk]

Just heard back from Lexus (Perth) - they've asked me to try out different fuels; I'm usually on BP Ultimate (correction: the car is usually on BP Ultimate) or the Shell Premium but this time I'll note down which fuel seems to emit the worst sulphur smell.

Kind of weird though - you'd think that a Lexus wouldn't be *that* picky with fuel, and surely there must be a better cat/fuel control mechanism to stop that much excess fuel being burnt up in the catalytic converter.

[Sapphire Cam]

C'mon guys - did anyone read my earlier post? Ive investigated this issue significantly, including calling Lexus Australia, speaking with my dealer several times and even emailing Lexus USA. My dealer did their own investigation.

My earlier post explains that it is a catalytic convertor issue, that Lexus USA are rectifying through the installation of new exhaust assemblies. Lexus Australia will not do this - much to the dealers' frustrations.

[dazk]

I read this was an issue with the earlier IS250's and a TSB was issued in the US to replace the catalytic converter with a new design -- why do Australian IS250 owners not get the new design? We're supposed to just put up with it when it's a known issue and there's a known fix?!

[Sapphire Cam]

Dazk - As I stated above, Lexus Australia seem to be the ones who are being difficult on this issue - much to the owners and dealers frustration. We're all not sure as to why?

[perks]

simple solution

get new exhaust system without the cats :)

"PTS Exhaust–Joe Z series '

[cevu]

simple solution

get new exhaust system without the cats :)

"PTS Exhaust–Joe Z series '

sounds like a good excuse to get an aftermarket exhaust!

nice choice as well!

[uad]

2008 sports, never noticed any smell whatsoever after hard driving!

[BIGW]

If the cats had collapsed (which is generally the reason for the sulphuric acid smell) your car would be running like a bitch.

Change out the pipes, or dont flog your car :)

[akuma]

i've got them too but i tense to ignore it.

[khoala]

dont flog your car :)

yeah right! hahaha

i get the smell too. I don't necessarily have to flog it, taking it over 4500-5000rpm and i can smell it.

something i can live with, but you think ;exus would have had it sorted.

Can anyone update with progress and if anyone has ever been able to get it fixed under warranty yet?

[kbx]

I spoke to Lexarse Oz today they denied any feedback related to it-So why not cut the cat converter out-sports exhaust!

[Atlantis]

> why not cut the cat converter out-sports exhaust!

Maybe the (up to) $62,000 fine from the EPA if they ever find out is enough of a deterrent.

You cannot remove the catalytic converter from a vehicle that is equipped with one from the factory according to ADR.

Edited November 22, 2016 by Atlantis

[2bling]

Just installed ISF xforce cat back (deletes the secondary cats) smell gone 100% my theory is the second cats dont heat up enough to burn the fuel only when you flog the car for 15 minutes then the smell goes and you get booked LOL just delete the cats job done.  

You can delete the second cats without being fined.

[imajames]

I've changed gas brands and also replaced the catalytic converter and the smell is still very strong.

The smell happens when I'm in stop-and-go traffic and than all of a sudden flog it.

Anybody find solutions to this?

[Stretch18]

Hello Lexus lovers ! The sulphur smell is a pain in the nose really but getting a new non genuine exhaust system fitted gets results ? Anyone know ? 

 

[bazzle]

Mine only smells when driven hard and I slow to a stop. 

BP doesnt have as bad a smell. I just live with it. Lots of Toyotas have the same issue.

[Neels]

Hi have the same problem on the is250. Exhaust smell in the car. Did remove the 2 cats after the 2 sensors. Now it is worse. Can't drive with the windows open

[Mark Normand]

I had a problem with the rotten egg smell and the cabin filling up with exhaust on my 2009 IS 350.The rotten egg smell was from my faulty o2 sensors needing to be replaced. 60000 miles is not a bad time to replace them ,but what do I know?As far as the cabin being full of exhaust everytime I rolled the window down, this is because there are two vents located in the trunk to allow air in to cool the amp and ventilate the trunk.Some how the vents stopped closing and started allowing exhaust fumes in since they are almost right next to both tailpipes.The exhaust ends up in the cabin from the suction caused by opening a window while driving .Plug these vents and there will be no more exhaust fumes inside the car.Took  a year and a half to figure this out.Someone online mentioned it.Thanks who ever you are.

[bazzle]

I added a link a year ago somewhere re the flaps. :). USA forum is where I found it.

As per my earlier post mine used to smell a bit. Nearly reduced recently it to zero with a can of Oxicat. Didn't think it would help but it did 🙂

Saw that too on the USA Lexus site with owners having success with it.

Must of been some crud on sensor and cat inlet side?

Oxicat | eBay

[ilv1004s]

its not a sensor or anything

its the secondary cats on the exhaust 

take it out or replace the mid pipes and youll be good

 

[bazzle]

On 10/2/2020 at 3:31 AM, Neels said:

Hi have the same problem on the is250. Exhaust smell in the car. Did remove the 2 cats after the 2 sensors. Now it is worse. Can't drive with the windows open

Neels post above mine tried the secondary cat removal with no success ?

[ghee]

Hi Everyone I'm  new here. Have an IS250 2007 and am having a bit of an issue with exhaust fumes getting into the cabin. I generally drive with all the windows up because of this problem. There seems to be a gradual seeping of acetone smelling exhaust coming into the cabin when I drive. If I put a window down it becomes overwhelmingly strong (brain damage anyone?) and I'll need to put all of the windows fully down for a while to try and flush it out and it takes quite a while to go away.

What I have already troubleshot: there are no exhaust leaks in the exhaust system, it operates silently. I have inspected the trunk and door seals as it must be coming from the tailgate and vacuuming back into the cabin somehow. I have inspected the spare wheel well and all over the inside of the trunk, no holes. I have removed the rear vertical backseats and checked the rear firewall double taping all around the conduit joins.

Notes: I always leave the 'closed'/recycled air con option on so as to avoid outside air being fed / creating an outflow for the exhaust vacuum to flow out of, i.e. leaving it shut so that it might help. However I still notice fresh outside air will flow a little through the vents when driving even with the fan off. I have checked the air filter in the glovebox and this carbon filter is relatively new and I have spare replacements.

It is proper stinky and a shame that living in a really nice climate that I can't roll with the windows down without enduring some mild asphyxiation.

I have access to an OBI if that might be useful. I'm willing to delete cat as suggested above, if that is the fix. Any suggestions would be greatly appreciated thanks!