I have a problem with my 2001 TJ GSR Sports, it often smells like a bad (rotten egg) fart!! Fuel economy goes out the window when this smell is present,ie; 14.5l/100km's around town; not good at over a dollar per litre! The smell occurs esp. when I am reversing or doing a 3 pt. turn and sometimes when cruising out on the open road. I am suspecting maybe the MAS sensor is faulty( have been told on fastmagna website that it maybe O2 sensors faulty, are these part of the MAS sensors? Excuse ignorance!) I am considering fitting K&N Ram pod air filter(oval type) and maybe Unichip engine management down the track. Any thoughts?

rotten eggs???

maybe something died in your engine...cat, rat or a snake?? :confused:

get it checked out..

with the rampod and ecu change, you'll def love the performance you get from it!! :D

my mums TJ Executive has the exact same problem, every now and then it smells like rotton eggs, havnt smelt it for awhile but it did do it for while

God, that must suck!

How in hell do you concentrate on your driving when you can smell Fart in your car? :P

i have heard once that when you burn crap unleaded at some weird rate it starts smelling like rotten eggs.

i dont know if that makes sense, but i have heard of somthing associated with fuel.

Yes, Rotten Egg smell is Sulphur Dioxide, which'll occur if you using crap unleaded or diesel, with high sulphur content.

if that's the case please tell us where that servo is so we can save some $$$ and you could maybe report this case to whoever controls petrol, etc....

Sounds like a dead catilac convertor to me.............mine smells the same!!!

mine's never had that problem, but i think i've only smelt it once, when i started the car in the garage with the door closed.

My dads KJ verada's got dat same problem, most notably when i drive it hard!!!! Smells like sulphur,,,or as u said BIG FART,,,,especially bad when i park it in da garage,,then gotta walk straight past da exhaust which is where da smell is coming from!!!! I heard its a common problem!

Cheers!

yeh my dads volvo gets it sumtimes, i havent had it in my car yet

Sounds like a dead catilac convertor to me.............mine smells the same!!!

He's right - usually the CAT-less cars or with a damaged CAT smell like that

I know it from the autocross, when the CAT-less EVOs are on the track everybodys looking around like......... "who farted?" :D

I have already had the catalytic converter replaced under warranty as the mitsu mechanic was confident this was the cause and while it improved for a short while it wasn't long before it was doing it just as bad. I haven't been back yet; I'll try premium unleaded first(or Optimax as I've heard it has an even higher RON rating than other premiums) then if nothing changes I'll get the O2 sensors checked. Thanks for advice guys, more welcome if more out there!!!

I am not sure it could be fuel related, cause we only fill up with premium unleaded fuels from caltex/shell and we still have that problem when we park the car. So yeah maybe the catalytic converter. any ideas on how much to replace them?

I also have this problem. Mostly notable when the car is under hard acceleration or load, i.e. going up hills etc.

Never smelt it in the car itself, but usally when I get out of the car after parking at home (top of a steep drive)....phwoaaarr...smells like a rotting cat stuck under the car or something...

Also happens if using premium too. I dont think its a fuel problem in itself as I get the small everyday regardless where I buy fuel from anyway :confused:

I do notice that it could be associated with poor fuel economy though, but then again hard acceleration and driving up hills will cause poor fuel economy as well. Hmmm gets me wondering wether it could be unburnt fuel?? Maybe the engine is being fed too much fuel (running rich)?? Anyway, I'm no expert, just a thought....

It could just be running rich.

My 3.0 TE does this too.

Where I lived last year I went up a large hill every day. It was in a 90km/h zone and it was boarderline 4th gear (instead of 5th) - The traffic always went 100 which was actually pretty hard to hold.
When going up the hill the car was pulling really hard, and almost every day I'd get the rotten egg smell.
I've never had it at any other time. No idea what it is - did someone say something about a bad O2 sensor could cause this?

-Dan

My mums TF 3.0 had (prolly still has) this smell after hard driving :badgrin: . My old TF has had this smell at idle only since the exhaust was fitted :confused: , and my new TF hasn't had this smell yet, even after long hard drives :D

STD Cat from Mitsu some 190 bux. Needs to be ordered tho. Bolt on obviously, easy to change. But faulty Cat would not affect the fuel consumption that much????

Thanks all for your thoughts; I am really thinking it's running rich with some problem with the MAS sensor( again does anyone know if this and the O2 sensors are one and the same?) 'coz I had the CAT replaced not too long ago and the problem persists. By the way chendur, I have the Sports type hi-flo CAT, the mitsu mechanic said they cost around 1500 bucks!! Got mine under warranty tho',phew! Something to do with having platinum within. I'll get sensors checked and let you's know the result. If this works it's onto the K&N ram pod and eventually Unichip ecu. When I can afford it that is!!

Definatly the CAT. Question is was has caused it to fail :shock:

Any unleaded car, when it is booted smells a bit like that. That is probably a combination of all the replies - running rich (full throttle), bad fuel economy (full throttle), etc. To get it to run rich and use fuel without full throttle, something is not functioning correctly, such as air flow sensor (on the intake, after the air filter), or the O2 sensor (on the exhuast, measures how much oxygen is left in the exhaust). When your O2 sensor fails, the car will run rich to protect it, as when they run lean, they run hot.

Yes, Rotten Egg smell is Sulphur Dioxide, which'll occur if you using crap unleaded or diesel, with high sulphur content.
This is sort of right. Sulpher dioxide (SO2) is odourless, but is an iritant that is known to induce asthma and other breathing difficulties. Yes it is emited from cars.

Rotten Egg (bad fart) smell is Hydrogen sulphide (H2S). Yes our fuels have sulphur impuriteis in them (mercaptans). H2S is also an irritant.

In the engine, fuel and air is combined with a high energy spark. This causes an explosion of gases, but also causes change of composition of all chemicals. In a clean running engine, it should produce H20 (water), CO2 (carbon dioxide) and CO (Carbon monoxide ...the silent killer ... a bit lik an SBD but without the bad smell :redface: ). The spark is enough to bond sulpher, hydrogen, oxygen and Nitrgoen (remember air is over 70% nitrogen) atoms together giving the molecules of H2S, SO2, but also H2SO4 (sulphuric acid responsible for acid rain), SO3 (responsible for smog - it turns into a brown gas in sunlight), Nitric oxide (NO) and Nitrous Oxide (NO2 - laughing gas, also marketed as NOS) (with vapour these can also become nitric acid ... also very bad).

The cat is a tube of platinum coated beads, when hot these change any unburned petrol into CO, CO2, and H2O, but also break down the natsy NOx and SOx in to more environmentally friendly compounds. The engine should produce more SO2 than H2S (the bad fart smell). Smell of bad farts is too much H2S and just may indicate poor quality fuel, engine operating at too high temperatue, or the Cat is on the way out.

Too much sulpher in fuel decreases the effectiveness and the life of our catalytic converters.

Stevo GSR - basically to fix this get the O2 sensor replaced - I know of 2 VR-X's that have had this same issue, replaced the O2 sensor, the car ran better, performed better, and didn't smell.

The O2 sensor is dead, and the car thinks it is leaning out, therefore safe gaurding adn pouring more fuel in and hence running rich.

Get it fixed at mitsu - this has NOTHING to do with the cat.

Manual

Definatly the CAT. Question is was has caused it to fail :shock:

Oh - and strangely enough on of the VR-X's was the one that is mentioned in this guys sig - yes it iwas Dan's / Cyphers VR-X that had issues with the O2 sensor.

Manual