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Sulfur Smell from Toyota 4Runner



  • nedzelnedzel Member Posts: 787
    Read the owner's manual. It specifically tells you NOT to drive with the rear window down. When you drive with the rear window down, aerodynamics causes the exhaust to be sucked into the truck through the open rear window. Even if it didn't smell like sulfur, you would be breathing the odorless carbon monoxide.

    Keep the rear window closed when you drive.
  • klaudnycklaudnyc Member Posts: 36
    Bought a 2003 SE V6 3 weeks ago.

    I just noticed the smell from my car yesterday when I did some highway driving with the tailgate window down. My back seat passengers complained of a really foul rotten egg smell. When I closed the tailgate window, it went away.

    Some of you have compained of getting the smell with the windows rolled up. I haven't experienced that problem, fortunately.

    But even so, what is the point of having a power tailgate window if you can't use it while driving? If Toyota doesn't do something (i.e. recall or post a TSB), I have to admit my trust in their name will be tarnished.
  • nedzelnedzel Member Posts: 787
    This isn't unique to the 4Runner. It is true of any vehicle with a back window. This is the well-known "station wagon" effect. It is simple aerodynamics. As the truck (or any station wagon) moves through the air, it creates an area of low pressure directly behind the vehicle. The air passing over the truck and under the truck will rush into the area directly behind the tail gate, as it tries to fill in the void behind the truck. Thus air from below the vehicle will curl up and into the truck if the back window is down.

    This was as true of a 1960s station wagon as it is of the 4Runner today.

    That is why, on page 29 of the 2003 4Runner's owners manual, there is a big yellow box labeled "Caution" that reads, in part: "Keep the back window closed while driving. This not only keeps the luggage from being thrown out but also prevents exhaust gases from entering the vehicle."

    Why does the 4Runner have a power back window? I find it more convenient than the flip-out windows used in some competing trucks.
  • renshorensho Member Posts: 42
    I did a 10 mi test drive with the rear window open ( to listen to the added noise) and never smelled sulfur once.

    So does that mean, you can never carry long lumber home from the store, or anything else that needs to stick out the back without smelling rotten eggs?

    As well as, people following you smelling it. I follow my friends in their new cars all the time going places. I never smell any terrible smells, as they not smell my 02 GTI.
    I didn't smell my friend's 96 4runner with the same open back window, open while driving.
    I bought this car specifically for my dog in order to carry her around so she can stick her head out the back. Otherwise, it would have been mdx, or rx300 all the way.
  • asdfasdf Member Posts: 9
    We can still smell it with all the windows roll up! Could be worst if the tailgate down, but my point is they are all up, UP, closed, Circ ON.

    In CA with 03 V8.
  • nedzelnedzel Member Posts: 787
    Even if you don't smell the rotten egg smell, you will get exhaust in the car. One major component of exhaust is carbon monoxide (CO). CO is colorless and odorless. And it is also poisonous.

    Like it says in the manual, roll up the back window when you are driving. Otherwise you will get exhaust in the car. Whether it smells like sulfur or not, exhaust is bad for you.
  • renshorensho Member Posts: 42
    Thanks for the education. We didn't realize exhaust is bad for us... ;-)
    Yes, CO puts you to sleep and kills you.

    My point is why does the 4runner emit so much sulfur smell? I'm a physicist. I can map out the vortex behind a 4runner travelling through the air very well. I understand the low/high pressure situation of the cabin and its relation to the opening of the back window WRT to exhaust coming in or not.

    Maybe we should agree to disagree on the issue of whether or not I should be able to drive with the window down.
  • swschradswschrad Member Posts: 2,171
    turn up the blower all the way and use a fresh air setting.

    under no circumstances whatsoever should exhaust get into a closed passenger compartment (he seethed, knowing full well that in traffic, the fumes from every other car in the road are pulled over the hood and into the car by the air intake.)

    if you're by yourself on the road and you smell your stinky exhaust, that is a safety problem with your car that the dealer needs to remedy under warranty. again, tell him I HAVE A SAFETY ISSUE WITH EXHAUST GETTING INTO MY CAR and see if they look awake this time. they are supposed to wake up for safety concerns.
  • nedzelnedzel Member Posts: 787
    You understand that exhaust gets into the car when driving with the back window down. The manual tells you not to do so. But you still think you should be able to do so? Ok, whatever.
  • tacovivatacoviva Member Posts: 116

    Go back and read the rest of this thread. I have the same problem with sulfur entering the cabin with the windows up and A/C on recirc. The fortunate thing abou the sulfur is that is lets you know that something/s wrong with the vehicle (can 't smell CO). I am scheduled to arbitrate on the 9th. Let me know if you guys need help.
  • tacovivatacoviva Member Posts: 116
    For those who care...here it is.


    I feel that the condition of Sulfur entering the passenger compartment of the vehicle is persistent and substantially impairs the vehicle’s use, market value and presents a health and safety issue. The condition appeared at delivery and I was told that this is common in new vehicles and this would disappear after the vehicle break in period. It did not. Finally, after waiting for several thousand miles, with the smell still present and stronger, I took the vehicle in to address to the problem and was told that there was nothing that could be done. In fact, Toyota of Ft. Worth and the Regional Customer Service Representative suggested I pursue the repurchase/replacement option immediately. Researching the problem, I have arrived at the conclusions below.

    Sulfur Dioxide (SO2) is formed when fuel containing sulfur is burned.

    Sulfur Dioxide has an odor threshold. What this means is that if you can smell it, the concentration can be determined. According to the Canadian Center for Occupational Health and Safety, the instant you smell Sulfur Dioxide the concentration is known to be 3-5 ppm (parts per million).

    Reference: Canadian Center for Occupational Health and Safety

    High concentrations of sulfur dioxide can result in temporary breathing impairment for asthmatic children and adults who are active outdoors.
    Short-term exposure:
    o reduced lung function
    o wheezing
    o chest tightness
    o shortness of breath
    Long-term exposure:
    o respiratory illness
    o alterations in the lungs' defenses
    o aggravation of existing cardiovascular disease
    People affected include children, the elderly, and those with cardiovascular disease or chronic lung disease.

    Ref: http://www.adb.org/vehicle-emissions/General/Health-sulfur.asp

    According to OSHA, The STEL (Short Term Exposure Limit) is limited to 5 ppm over 15 minutes of exposure. Therefore, if the odor threshold is 3-5 ppm and the STEL is 5 ppm, then if the smell is present in the vehicle for 15 minutes of driving, then the Government standard for exposure has been exceeded. This has occurred on a regular basis since delivery of the vehicle.
    Reference: Safety and Health for Engineers, Roger L. Bauer, ISBN 047128632-X

    Hydrogen Sulfide (H2S) is the byproduct of the fuel containing Sulfur.
    Eye Effects: Low concentrations will generally cause irritation to the conjunctiva. Repeated exposure to low concentrations is reported to cause problems, including tearing pain and blurred vision.

    Inhalation Effects: Continuous low level exposure will generally cause irritation to the mucous membranes, and may also cause headache, dizziness, and nausea. Continuous low level exposure also causes olfactory fatigue. Thus, detection by exposed individual may be ineffective.
    STEL (Short Term Exposure Limit): 15 ppm
    Reference: Hydrogen Sulfide MSDS.

    I’m employed by a major Engineering company in FT. Worth, Texas. While employed here I’ve dedicated a considerable amount of time as a Safety Engineer performing analyses such as this for the various programs. The data used in this analysis is readily available and well documented. Furthermore, the smell is extremely unpleasant and as such reduces the value of the vehicle. Therefore, I respectfully request that Toyota repurchase or replace my vehicle.

  • vaughn4vaughn4 Member Posts: 106
    I dumped my 4Runner after 6K. My biggest concern was that it was dangerous and that the truck would be worth a lot less if I kept it and word of the sulfur problem (INSIDE THE CABIN) gets out to the general public. Again, I'm talking about INSIDE THE CABIN sulfur odor - Who cares what it smells like on the outside? No vehicle should smell the way mine did inside the cabin - All windows up & A/C on recirculate. This is a health and financial issue. Amazing!!!
  • coranchercorancher Member Posts: 232
    We've been talking mostly about those who get the sulfur smell while the air system is on recirculate. I don't remember much discussion of smell experience when the intake was was on fresh/outside instead. I don't know where the cabin exhaust ports are, but I suspect they're at the rear of the vehicle. Could this be a significant factor? Is it very common to have the smell problem while moving down the road and having the button in the fresh/outside position?

    Also, I suppose that carbon monoxide is always a potential problem, but my understanding is that modern engines with oxygen sensors and closed-loop mixture control systems don't produce appreciable CO. CO is a byproduct of incomplete combustion and the modern systems set the mixture up for very complete combustion if they're running correctly. Of course, even a little CO produced on an occasional basis might be a problem, as the body is very slow at getting rid of it.
  • vaughn4vaughn4 Member Posts: 106
    My odor was present with or w/o the recirc on. Both fresh and recirc - It still smelled like a rotten-egg factory. All for about $30K - What a deal!!!
  • rokinkrokink Member Posts: 25
    Put the A/C on manual (like most other cars are usually set) and recirculate the air, then accelerate like hell and back-off the accelerator. You wil find that there is no sulphur smell in the cabin.

    In auto mode, some amount of outside air is let into the cabin.
  • tacovivatacoviva Member Posts: 116
    All vehicles are required by law to allow some amount of fresh air in the cabin even on recirc. Vaughn4, I agree that you should never, under any circumstance, have any emission inside the closed vehicle.
  • sacstate1sacstate1 Member Posts: 189
    I was walking through the parking lot on my way into the office. A co-worker pulled into the lot, drove by me, waved, parked and then WHAMMO! Talk about a nauseous, horrible, wrenching rotten sulphur smell! My eyes and nose were burning just standing there listening to the engine idle. The car: '03 Honda Accord V6.

    This claimed smell is not a Toyota only issue.
  • micksdad1micksdad1 Member Posts: 32
    Gotta tell you that this sulfur issue now has me concerned. I was hoping to put my yellow lab in the back and ride with tailgate window lowered. One poster is saying that the owner's manual says you shouldn't drive with the rear tailgate window open. Now I'm seeing postings where people are experiencing the sulfur smell with the windows entirely closed! Is this something I'm going to detect immediately when I test drive the vehicle that I hope to buy or lease? or should I just forget about the 4Runner and go with the Acura MDX?
  • renshorensho Member Posts: 42
    The sulfur smell was really bad on the drive home from dealer. Since then, it is less, a lot less. My nose is not great, so...
    On the initial drive home, with the rear window open and front window open, the smell was horrible. Since then, I don't drive with both open, so we have 2 unknowns.
    I'll try with both open when i get a chance today.

    Again, I'm in CA, so if others are right, our state has the least chance of the problem. I feel for others in the higher sulfur content states. (although your gas is likely to be less expensive)
  • nedzelnedzel Member Posts: 787
    micksdad: I haven't noticed any smell in my truck, but I've only had it for a week. Some folks do have it, but it does not appear to be universal.

    However, you should not drive in any SUV (whether the 4Runner or anything else) with the tailgate window lowered. That will be just as true of the MDX as the 4Runner. Even if you get a 4Runner and don't have the sulfur smell, you still should not drive with the tailgate window lowered.
  • rokinkrokink Member Posts: 25
    If the law requires that some amount of outside air is permitted into the vehicle, can someone explain how exhaust can be prevented from entering the vehicle? With a 100 foot long tail pipe maybe?
  • swschradswschrad Member Posts: 2,171
    the general idea is that you don't take in air and exhaust the engine fumes near each other. unless you have a strong tail wind, you should not be fouling your own nest, but everybody else's. if you are stinking yourself out of your own car, there is a lack of body integrity (oh, so polite... also known as a freakin' big exhaust leak) that is disturbing (also known as a killer leak.)

    so I have two worries reading these posts... one, inadequate or ill-suited treatment of the engine wastes in violation of EPA air quality rules and DHEW health and safety requirements... and a car design about as proof against gassing the driver and passengers as the 1961 corvair.

    somebody show where I am misinterpreting this, I would like to know that we don't have a major automaker this derelict.

    yes, I have an ax to grind here, I'm asthmatic, and I want all the stinkers de-stunk. all of 'em. whatever it costs the manufacturers to do this, they need to spend it. now.
  • tacovivatacoviva Member Posts: 116
    Rokink, If you mean to sound ridiculous, you've succeeded. Sulfur doesn't have a physical compulsion to air vents. So I don't think a 100ft tail pipe would work. You could try though. If you do, post the photos.

    I suspect,as swschrad does, that there is a body integrity issue here that is sporadic in nature and not easily or cost effectively repaired. Any more folks with this problem please post.

    Also, I plan on printing this board out and presenting it at my arbitration. Can I do that, legally?
  • swschradswschrad Member Posts: 2,171
    remember, it's not the opinion of Edmunds, it's the opinions of a bunch of us little guys that collectively make up the economy.

    hey, I like the sound of that. gin up a flag, raise an army, and I got a future ;)
  • zueslewiszueslewis Member Posts: 2,353
    I said some things about "cases going down in flames" that would certainly influence arbitrators, especially considering my position in the court system.

    Be careful about what you copy.
  • micksdad1micksdad1 Member Posts: 32
    Taco, the postings on this board would constitute hearsay. However, you should check the rules of the arbitration proceedings on whether the postings would be admissible. Ordinarly, in a court of law, even signed, notarized and sworn statements will not carry the day. The rules of evidence generally require live testimony in order to allow the other side an opportunity to cross examine the witness's testimony.
  • klaudnycklaudnyc Member Posts: 36
    A few people have posted the idea that the presence of sulfur is beneficial because it alerts us that CO is present.

    I have to disagree with that argument by reason that the sulfur smell only occurs sporadically. Your argument would make sense if the car emanated sulfur odor 100% of the time so that the driver would always be alerted to CO. But that is not the case. Why would Toyota fabricate an odor emanation warning system to work unmethodically? Are we in any danger of passing out from CO poisoning if it weren't for the warning smell of sulfur? Clearly not. I firmly believe that this problem needs to be addressed by Toyota. The fact that this message board exists is enough testimony to that.
  • zueslewiszueslewis Member Posts: 2,353
    is when someone goes into a lemon law or breach of warranty hearing, the concept is that your vehicle is unique in its problems and they should make amends with you.

    Bringing in the posse to show that 100 people are having the same problem takes away the "uniqueness" of your case and usually disqualifies you from any legal proceedings.

    Tread VERY carefully...
  • tacovivatacoviva Member Posts: 116
    I want to do this right and that's why I asked. I agree that I need to make a case for myself and present it as unique. Once he smells it, it's over. Hopefully he has a small child or children and will be sympathetic to my concerns.

    The comment regarding the positive side to Sulfur being in the cabin was that, if it wasn't there, we'd be none the wiser. The point: I'd rather find out that my car has an emissions leak by smelling Sulfur than passing out from CO poisoning and running into a light pole.

    It's similar to the addition of sulfur to acetylene; thereby alerting the welder of a potential hazard.
  • zueslewiszueslewis Member Posts: 2,353
    you REALLY need to act like you're the only one who has ever had this problem.
  • swschradswschrad Member Posts: 2,171
    supporting documentation should be as close to the originals as you can practically get.. for example only with assuredly bogus numbers... if you found an EPA document DOA-666 that referenced toxic levels of sulfur dioxide, you determined the stink compound you had was sulfur dioxide, and wanted to present that information as supporting evidence... an abstract pulled off the ACS web page may not be enough. an abstract with the original EPA document pulled off their website would provide the original claim, plus a "cliff's notes" summary for a quick view of the information.

    if this was a bar bet, you could get away with a lot less. the amount of the claim is somewhat larger than small claims, and certainly up where felony fraud is counted in every state, so the wisdom of preparing evidence for firm effect and covering your backside should be easily seen.

    you have stated earlier that you perform risk reviews and so on as part of your living, tacoviva, but some drift-by web readers may not appreciate as you do what constitutes good scientific and legal evidence. thus I am belaboring the point for the others.

    our self-selected non-scientific sample of thoughts may be good tips on things to chase that might provide further solid evidence documenting your loss. I doubt that the Supreme Court is going to quote me in its next session as an authority ;) might get some high-fives if you hang it outside your cubicle, might not.
  • tacovivatacoviva Member Posts: 116
    I'm preparing a presentation with all the approproate references, e.g. OSHA, NIOSH, MSDS, etc. These are the same standards that Toyota is legally obligated to follow here in the US. I want to first prove that the emissions are in the vehicle and that should be enough to prove the value of the vehicle is affected. However, the safety concerns need to be addressed as well. Aside from the monetary aspects of the case, a hazardous condition takes a considerable amount of time, effort and not to mention resources I don't have. Hopefully, I plan on winning based on loss of value, then give Toyota something to think about.
  • zueslewiszueslewis Member Posts: 2,353
    The primary portion of my job is to place a demunition in value on vehicles involved in lemon law and breach of warranty cases (with bad service histories/repetitive problems) - it's 90% of what I do.

    To prepare yourself, you have to determine the amount of the devaluation and the actual breakdown and reasons - you can't, as a consumer, just say "I've lost $5,000 because I think so".
  • tacovivatacoviva Member Posts: 116
    The devaluation comes in at resale. A vehicle will be worth less if it has emissions in the passenger compartment. And possibly it could be worth nothing at all if it's a proven hazard. Correct? So a total loss isn't out of the question. In fact, if you know someone at NCDS or ISG, ask them and they will tell you that Toyota is buying or replacing the 4Runner.

    If I build widgets and say, Lot 1 was produced with faulty parts, then those widgets in Lot 1 are worth less than the other Lots produced (assuming the problem is fixed). It's like PCs with Celeron processors. They are basically chips that didn't meet spec (the yield is lower) to be called P4s, as a result they are devalued by a certain amount and sold.
  • zueslewiszueslewis Member Posts: 2,353
    for a living.

    Proving the hazard, not just your assumption of a hazard (meaning with test equipment, not just a sensitive nose), is the key.

    What I've been saying is that based on many, many vehicles giving off sulphur smells, in my opinion, there IS NO devaluation. I've seen several cases like this get nipped in the bud and the firm quit taking them.

    I wish you luck. Without proof that noxious levels of gases are entering the cabin, there's no case.
  • alfster1alfster1 Member Posts: 273
    on my '03 Runner limited, I only experience the sulfur smell when the rear cargo door is open. Does anyone know if Toyota has an explaination for this? When I call the Toyota hotline, I either don't get through or am not given an explaination.
  • zueslewiszueslewis Member Posts: 2,353
    the vehicle with the rear cargo door open?
  • swschradswschrad Member Posts: 2,171
    some folks just don't get the message that airflow around and over a car is going to pull exhaust into the car through an open tailgate.

    the only advice I have ever seen if you have to do it to bring some lumber home from the yard is to crank up the blower to full power, and/or open some side windows.

    and I can tell you, there will still be some exhaust coming to you even if you have the air vents blowing bugs at you like you were on a motorcycle with no wind shield and no helmet.
  • mhallackmhallack Member Posts: 32
    "What I've been saying is that based on many, many vehicles giving off sulphur smells, in my opinion, there IS NO devaluation."

    I think Tacoviva has a point that not many other vehicle owners have had. Based on his description, his vehicle actually sucks the exhaust gasses in, even with the rear window up and the system on re-circulate. The vast majority of other owners who have weighed in and claimed to have the issue stated that their rear window was down...a totally different circumstance and, IMO, not likely to be an actual defect.
  • zueslewiszueslewis Member Posts: 2,353
    my point is without proving the "substantial impairment of use, safety or value" through instrumental testing on the sulphur smell, and a determination that it is at a dangerous level, all you have is a smell - one that is present in many, many vehicles.

    The whole concept of lemon law is the uniqueness of YOUR vehicle and its problems.

    If you can't prove toxic levels of emissions are entering the cabin, all you have is the fact that your vehicle gives off the same smell that 2 out of 10 vehicles on the road - and you're not unique in your situation.
  • tacovivatacoviva Member Posts: 116
    Sulfur Dioxide has an ODOR THRESHOLD = 3-5 ppm. If you smell it, then it's concentration is AT LEAST 3-5 ppm. That's directly from OSHA (Canadian). Once the concentration is established, all you need to do is prove that 3-5 ppm is a hazard. Again, read the MSDS and OSHA regs on the STEL. You'll find that it's 5 ppm = hazard. Especially for 5-6 years of exposure. Furthermore, it's unpleasant to be around (irritates eyes and smells terrible). Also, IO can't think of one brand new vehicle that has Sulfur emissions INSIDE the vehicle. Can you?

    Is it up to me to hook my instrumentation up to my vehicle? I don't think so. Toyota has admitted the presence of Sulfur INSIDE the passenger compartment, now I believe that THEY are responsible for showing that the concentration does not violate the STEL per OSHA spec. Where I work, If our customer discovers a potential problem, we spend our resources to determine the hazard risk level. I understand your position, however, if you drive one of these stinkbombs, you would certainly think that it's highly objectionable.
  • zueslewiszueslewis Member Posts: 2,353
    like that and agree with you - all I'm saying is that YOU have the burden of proof, by law, to prove your case. Toyota's defense doesn't have to do anything to disprove it. You have to PROVE it.

    After 3,500 cases in 2.5 years, I know how these arbitrations work - I'm just trying to let you know what you need to do - I'm not saying it's right or wrong, it's just the way it is.

    The plaintiff has the burden of proof - period.
  • renshorensho Member Posts: 42
    I think what he is getting at is, consider the smelling VS non smelling as subjective. Imagine taking the service manager along for the ride in your 4R and you saying, 'see, smell that?' He says, 'No, i don't smell anything.'
    With a meter, it doesn't really matter if your sulfur olfactory threshold is 500ppm, and his is 500000ppm. The judge here cares about your measurement and your 3-5ppm OSHA doc.
    just a thought.
  • alfster1alfster1 Member Posts: 273
    The only reason I drove with the cargo window open was to see if I would experience the Sulfur smell that others reported. I don't normally drive with it open.
  • tacovivatacoviva Member Posts: 116
    Thank you all for advice. It's easy to smell. The customer service rep even admitted that he and his wife smell it.
  • puckyhuddlepuckyhuddle Member Posts: 52
    The common answer given to the sulphur issue seems to be that it will disappear/diminish after 10K miles. Has anyone found that over time the severity of the smell decreases? Is it still a problem for many people at 10K + miles? Thanks.
  • swschradswschrad Member Posts: 2,171
    the warranty is over and nothing happened.

    horse dovers, I say. burning fuel loads the cat up with sulfur, burning more isn't going to clear it.

    sounds like fancy dancing while herding you towards the door to me.
  • tacovivatacoviva Member Posts: 116
    I agree, that sounds like puckyhuddle! JK. It's a problem they can't fix. Return the vehicle if it bothers you.
  • meyersejmeyersej Member Posts: 13
    I just posted over in the regular 4Runner forum. I had the sulfur smell too and switched over to premium fuel for a couple of tanks and the sulfur smell is gone. Unfortunately it's been replaced by an ammonia smell, but it's nowhere near as strong as the sulfur smell was and is only noticable when the rear window is down. It seems to be subsiding as I get more miles on the vehicle... I've got 900 miles now.
  • tacovivatacoviva Member Posts: 116

    Do you understand that you should never have emissions inside the vehicle, including ammonia.
    So premium is required now to go from Sulfur to ammonia. If it weren't a hazard to your health I'd say that sounds rediculous; however, it's anything but.
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