Conference terri::cars_uk

    
    Check out the CARBUFFS conference.
    
    Rotting eggs on Cat equipped cars is a VERY common problem. I can't
    remember the reason, but CARBUFFS will be able to tell you.
    
    Push for the Turbo, it'll be much more fun!
    
    Mark

    My BX TGI has the same problem.
    
    Sometimes the Cat. converter check light goes on.
    I assume it's either engine management adjustment or replacement.
    
    Hans

As far as I remember, it's caused by sulphur in the fuel, which ends up
as Hydrogen Sulphide (H2S), or some such. Most schoolboys have 
produced the same reaction in the chemistry labs....

It depends on the blend of fuel, and where it was dug out of the ground.

The only suggestions I've heard in the past is change your normal brand,
and run a different one for a couple of tankfuls, and keep changing until
you hit one with a lower smell/lower suphur content.

However, if the blend changes, it might come back again.

Look on the bright side; every one now knows you have a cat, and are
saving the world at the same time as you poison yourself....

Here in the US, people whose cars are suffering a lot from this problem are
often advised to change their brand of fuel. Some brands/some blends have
higher levels of sulphur impurities, which can lead to the catalytic converter
producing hydrogen sulphide (the 'rotten egg' gas).

Try filling up with another brand of petrol.

John

    Hi
    
    Many thanks for the replys.  I should stress that if the pong was
    limited to the outside of the car I probably wouldn't mind.  The pong
    is comming in through the air conditioning.  When I say pong I mean
    real PONG.  The garage have suggested other types of fuel, which I have
    tried (no difference).  
    
    Regards
    
    Bruce

    Bruce,
           have you got a cat in your office as well..???
    
    'cos there ain't half some nasty pongs in there as well...

    Bruce,
    	I remember smells such as the rotten eggs emanating from yourself
    
    long before you had your new car.Have you checked yourself with
    
    the doctor????

    Well thanks for the hints  chaps.
    
    I want you all to know that I have been "curry free" since  before the
    car  came  along.  Even I could not possibly boast a smell like this 
    car produces. 

    
    On this problem,
    
    I noticed it myself for the first time on Saturday. I was following a
    4-something-0 Volvo and noticed it had a Catalyzer badge on it. As I
    got closer I also noticed that it had the very significant smell of 
    rotten eggs, not at all pleasant. It must have been really bad as the
    vents were all shut as was the sunroof and the windows.
    
    Mark

    My Calibra has a convertor.... I have noticed 2 (maybe 3) times when
    getting out of the car that there is a "different" smell coming from
    it.
    
    Never has it been noticeable inside the car. Never has it been worrying
    - just different. Up to now I have assumed it was hard driving or hard
    braking shortly before getting out... now I will look/smell more
    closely. (I thought hard braking because it seemed to be similar to the
    smell that comes from 125 trains when they brake hard).

    Chris, Is your Calibra an 8v ? what sort of mpg do get ?
    I understand that these 'cats' can cause poor fuel economy.
    
    - Roy

    My Astra (16v) has a "Cat".  It doesnt smell, regardless of what fuel 
    I put in it.  It gives me about 38 mpg with enthusiastic use of the
    full rev range (lots better than the Pug was in this respect).
    
    
    John

If these smalls are are as common as seems to be suggested, I think that it 
may be advisable to invest in a deodorizer or nose clip.  As from the end 
of this year *ALL* new cars will have catalytic converters in order to meet 
the new exhaust emission regulations.

jb

My Alfa's convertor gets *unbelievably* hot, even after relatively short drives.
Not a sign of impending failure - at least I think not as it was checked not 4
weeks ago!

I do remember rotten egg smells in the US back in the 70's when convertors were
first introduced, but there's no smells over here now.  So what's different/
changed?

Brian

    Hot converters: very normal; beware: you might introduce forrest fire
    with such a converter.
    
    Rotten egg fumes: In Europe we are far behind USA!
    In a local newspaper was an article about ELC (Evaporate Loss Control)
    systems to be introduced.  An American company is coming to Europe
    to manufacture the active carbon filters overhere.
    
    My 20 year old US spec MGB already has such system...
    
    
    Hans 

    I've had some nasty niffs coming from my Astra a few times.  I think
    it is a result of shopping at Tescos at Chineham.  I've never had
    any trouble with Texaco.
    
    TP

>    My Astra (16v) has a "Cat".  It doesnt smell, regardless of what fuel 

Maybe you should ask the people following you when you are driving along...

Cars with cats are very identifiable from behind !

;-)

    I hotly dispute the fact that I am "restrained" ;-)  The worst figure I
    have returned is about 34mpg, on a 300 mile motorway trip at a bit over
    4500 rpm in 5th (I dont go faster than that in the UK cos I dont want to 
    attract too much attention of an official nature).
    
    38mpg is on my normal run into work of 12 miles of not too busy country
    and A roads (with enthusiastic use of the full rev range where safe), 
    then 4 miles of the M4.  38mpg is also motorway cruising at 4000rpm.  
    Even at this more modest speed, I find that only one or two cars pass me 
    on a 200 mile motorway trip.
    
    I dont know what I'd get If I did lots of stop-start driving.  The
    previous noter (sorry, forgot who you are) with the low mpg figures 
    may benefit from getting the SFI system checked out. 
    
    I'll try to remember to do an accurate check of what I get from my
    next tankful.
    
    
    John

    Hi
    
    Well Toyota's stance on this subject is as described to me in person in
    front of their dealer and a representative from Hertz.
    
    a) Yes we (Toyota) accept that the "Cat" does give off a smell.
    
    b) Toyota are not alone in this.  Volvo have similar problems.
    
    c) The problem is the fuel used in the UK not the car.
    
    d) We Toyota can see no way to resolve my particular complaint.
    
    e) We Toyota believe that the problem will "improve" with useage. 
    Possibbly around 10,000 / 15,000 miles.
    
    The lease company seemed unwilling to terminate the lease, as they
    did not find the smell as un-pleasant as I do.
    
    MY OPINION !!!
    
    I would not buy or lease another Toyota, mainly as a result of their
    "unsympathetic" attitude to my problem.  I also have severe
    reservations about Digitals abbility to do the "right thing" as regards
    employees who are suffering from "car problems".
    
    Some other interesting snippets of conversation gained from Toyota UK's
    Technical Department.
    
    "Toyota Motorsport is NOTHING to do with Toyota, we just give them the
    cars."
    
    "Lots of people have bought Supra's and have noticed this problem,
    blame the Fuel Companies not us".
    
    " If you have the windows up, and do not do alot of stop/start driving,
    you shouldn't get the problem, but if you reverse it may get worse"
    
    
    Sounds like a John Cleese Video I saw once wher he accuses the unhappy
    Customer by saying "you've been using this haven't you ??" 
    
    
    Regards
    
    Bruce

That'll teach you to buy a Nippon tin box!

	Best giggle I've had in a while!

	Heather

    Back to an earlier question - mpg in a Calibra 8v.
    
    I find that I get between 32 and 34 to the gallon. It could easily drop
    to 29-30 if I had fun for a whole tankful, but normally a mix of
    driving returns 33.
    
    My previous car (Carlton) I found that long motorway journeys at 90ish
    were as heavy as short town journeys (a lot of car to push through the
    air). This is not true with the Calibra - very frugal at speed -
    although my overall figures don't reflect this!. 'Cos after a motorway
    jouney I usually find myself booting it along country roads - or
    dawdling through London!
    

	I had a Toyota Supra as a leasemobile, great car, only reason I didn't 
get another was that my wife wanted a car with four seats, not 2+2.
Didn't get any smell,but then. it never had a Cat. Guess this was the reason!!!!

	Now have a Carlton GSi, with Cat. No smell. Guess I picked right!!

	But fuel consumption between Decpark and Burghfield, whew.

	Ken

    Well here is the latest.
    
    Hertz leasing under pressure from Car Fleet and my good self, agreed to
    test my car for a few days.
    
    Well one afternoon proved long enough for their hooters.  I got a call
    the following day from Hertz.  They tell me that my car smells.
    
    They also tell me that Toyota have agreed to remove the Catalytic
    Convertor, and can't understand why their Technical People said that it
    could not be done.
    
    Toyota also now insist that the engine management will not be affected,
    despite this being their original argument.  I don't know who to
    believe now.  But I do know that I would never deal with Toyota by
    choice again.  In my opinion their attitude sucks.
    
    Regards
    
    Bruce

    I've got a Cavalier GSI, and I got the bad eggs smell every now and
    then. However I never really did anything about it until about a month
    ago when I saw a program on TV (maybe Top Gear?) that described the
    problem and put the blame down to the sulphur in the petrol reacting
    with the chemicals in the cat to give off H2S.
    
    Their recommendation was to shop around for petrol until you find the
    least smelly brand - as already discussed in this note.
    
    I used to fill up at Tesco's in Chineham (because it was the cheapest),
    but for the few weeks I have been using Shell petrol (which is now
    cheaper than Tesco's) and no smells so far. 
    
    Greg

The cure is to have a converter element that includes nickel in the coating.
Nickel catalyses the oxidation of H2S to SO2.  Having nickel is standard 
practice in the US; in Europe it appears that the Germans object so over
here the converters generally have no nickel.

jb

 
>    I used to fill up at Tesco's in Chineham (because it was the cheapest),
>    but for the few weeks I have been using Shell petrol (which is now
>    cheaper than Tesco's) and no smells so far. 
 
Where?

Jc

    Well
    
    Silly of me getting all excited expecting my car to get put right.  I
    am still waiting on Toyota to manufacture the exhaust.
    
    Hertz can't/won't take any further action, than continually phoning
    Toyota and complaining.  Toyota for their part ignore this.  and why
    shouldn't they they have the dosh for the car.!!
    
    Car fleet can do no more as it is in the hands of Hertz.  In the mean
    time I keep on paying for a car that I have complained about since day
    one.
    
    Does anybody out there have some solid "legal" advice as to my rights
    in all this mess.  Surely I should not have to suffer like this through
    no fault of my own whilst still paying for the car.
    
    Regards
    
    Bruce
    
    

    My wife is now the owner of a new Renault Clio with a catalytic
    (sp?) converter which is driving her mad.
    
    The problem is the smell - hydrogen sulphide (?) aka rotten egg gas. 
    She only uses the car for short 3-8 mile journeys, just enough time for
    the cat to warm up but not long enough to clean out the exhaust system.
    
    Does anyone know of any magic cures to stop the smell - I have heard
    that there is a petrol additive which is supposed to help.  Does it get
    better or worse with time and mileage?
    
    Any help appreciated.
    
    Cheers,
    
    Gerry
    

    
    RE-1
    
    	A Feu orange!
    
    
    Andy

    Mine does exactly the same, I thought it was a feature of a "cat"
    because everyone keeps asking if my car has a cat or can I smell rotten
    eggs!!!
    
    Be interested to know if there is a cure though!

    Mine smells a bit funny just after start-up, but I've never had the
    rotten eggs others have complained about.
    
    In the owners manual it says you shouldn't "warm" the engine up before
    setting off, but go straight away - might this help?
    
    Also, I use Super Plus Mega-Go High Priced Unleaded, as it is supposed
    to be kinder to the Cat.
    
    Does anyone with a diesel cat (yes, they do exist) have eggy problems?
    
    Andy

    I'm awaiting my turbo-diesel-with-cat (SEAT TOLEDO) should arrive
    mid-june.
    
    I'll let you know if this has the characteristic cat smell or something
    worse.

    The bad egg smell is Hydrogen Sulphide. How bad it is depends upon how
    much sulphur is in the petrol. The usual suggestion is to try other
    brands. At 5 miles a trip this could be a long slow experiment.
    
    Andrew

    
    My wife and I both have "cat" cars (a renault 19 16v and a Lada Samara)
    my wifes Lada does have a bit of a funny smell but only noticed when
    you've just pulled up and only outside the car, and I wouldn't describe
    it as a problem ....nothing like rotten eggs....as for mine I've not
    noticed any smell at all, and I just run on the cheapest petrol I can
    get.
    
    Richard (young)
    

Not so much a bad smell... but does it do any good?
    
Hypothetical question:  Might a simple way of increasing fuel consumption/power
be to remove a catalytic converter?  The case in mind is for a car used mainly 
for short journeys, i.e. where (rumour has it) a catalyst tends not to warm up 
enough to perform its intended function properly. Hence, with the cat removed,
the car might well be no more polluting than before.

To expand:
- How obstructive is a catalyst in a modern car?  Would the more free-flow
  exhaust amount to anything significant?
- Assuming that removing the cat was done simply by sawing out that section of
  the exhaust (say x2, assuming twin exhaust, twin cat), and welding in
  ordinary tubing to replace, is this likely to mess up the exhaust pipe
  tuning, resonances etc., hence maybe actually *degrade* performance?
- Might the fuel injection have to be recalibrated, or should a modern FI
  and ignition system (exhaust oxygen sensors, anti-knock sensors etc.) be able
  to compensate automatically?

I realise that environmentally safe disposal of a catalytic converter is an
issue in its own right.
    

    Before you rip out the back-box of the exhaust you should check that it
    really is the location of the catalytic converter. My Cappuccinno has
    the cat placed about 8 inches from the manifold. The theory is that
    this will heat up quicker I suppose.
    
    Barry.
    
    PS. The other alternative to butchering the back-box may be to buy a
    replacement exhaust from an earlier model of the car (if an earlier
    model ever existed). Also, if its more perfromance you are after then
    a new specialised manifold may help. People like Demon Tweeks could
    give you a lot more help. Put the feedback in here though!

    1.	The 2.0l 16v Vauxhall engine as fitted to 16v Astra's Calibra's
    Cav's produced 156 bhp before they fitted a cat and 150 afterwards.
    (it's now down to 138 with other "eco" features!!!!!!)
    so that's around 4% reduction by the cat.
    2.  Is there a problem disposing of platinum ?
    
    3.  Isn't there a law about cars after a certain date having to have a
    cat? rather like rear seat belts?
    
    Matt.

    
    The 138 Bhp 16v 2.0 isn't the same engine as the Astra 16v engine.
    
    The main feature of the 138 Bhp engine is a flatter torque curve, which
    is more suited to the Calibra.
    
    Mark

    In my opinion.... Flatter torque curve = more boring engine?
    and is just marketing garbage to help not put off customers when
    they reduce cost or improve emmision control.
    
    If you reduce comp ratio for instance then you will get less
    top end power but a wider power band and a flatter torque curve?
    This is not most people's idea of a "performance " engine and is more 
    suited to commercial vehicles, taxis etc.
    
    Anyway rathole alert, wasn't this about cats and other furry creatures?
    
    Matt.       

    
    re:.45
    
    If it's the same ECOTEC 2.0 they put in the Cavalier it doesn't come
    alive until 4.5-5K revs...dunno where the torque curve on that is flat,
    or is it me that doesn't understand the technicalities?
    
    Chris.

    
    Before you brand all torquey engines as non-performant, try the Renault
    5 GT Turbo (hardly worth revving above 4k) or the Rover T series 2
    litre (great punch out of corners).
    
    These high revving engines are fine for race cars and multi-lane roads,
    but lots of low down grunt makes a car untouchable on twisty roads
    (provided it handles, of course, which Calibra's don't really, no
    matter which engine they have.).
    
    Mark

    re .48
    
    I second that comment regarding the Rover 2 litre T16. Max torque at
    2300rpm (160ftlb I think) and 136bhp. The trusty Vauxhall 2litre
    16valve hit max torque at 4800rpm (???ftlb) and 150bhp. Having had
    experience of both, I'd take the Rover any day, a afr better
    performance engine for touring at speed.
    
    Clive

the old Ford CVH engine had a flat torque curve, between 4500 and
4503 revs.  Horrible to drive!

Chris.

    S'Funny but the 8v Calibra engine has max torque at 2500rpm,
    significantly lower than the 16v engine.

    My Mazda MX5 1.8i produces max torque 152Nm @ 5K (thats 112Lbft for the
    non-metric) and at 2k its producing 140! Not bad for a 16V.
    
    When combined with the close ratio gear box it's a very flexible unit,
    pulls very well from 15MPH in 3rd & 20MPH in 4th.  
    
    Rathole
    I also suffered (my last?) humiliation on a roundabout, last night, when 
    I lost the back end in the wet last night. Although it was a minor shock,
    the car recovered very well. Might be as well to get a course on a skid 
    pan before winter.
    
    Dave  

>>>to get a course on a skid pan before winter

I know this may be a controversial and revolutionary concept, but why don't you 
save the cash, and *drive slower*?

	A skid pan course is not a bad idea; you can do it yourself
	on an icy morning in the car park but there aren't enough
	of those in the UK.  By the way, nicely balanced rear wheel
	drive gives rear end drift but too much drift equals a skid
	when the back end snaps out.  You have to come off the power
	to correct it.  A lot of people seem to dislike rear wheel
	drive cars for this reason; however, that's exactly why I like
	them.

	Dave

    Hoorah to that!
    
    Dan

    I'm with .54, I much prefer RWD, for that very reason.
    
    Laurie.

    Re last few
    
    I have only had the car for two weeks and still exploring its
    limitations. In the dry it sticks to the road like s**t to a blanket, the
    incident last night was my own fault, a combination of inexperience, 
    light drizzle and too much throttle in 2nd. I was travelling no faster
    than 35MPH.
    
    The humiliation concerned the large juggernaught I was try to pass on 
    the inside. The driver ended up in fits laughter whilst I felt suitably 
    silly.
    
    I think the skid pan course would be money well spent as it would be
    an opportunity to explore the cars wet handling characteristics in a safe
    environment. It will teach me how to react in situations like this and
    help prevent me causing an accident which may have involve others.
    
    Dave
     

    Re: .52   I've had an MR2 and a '90 MX5 1600 and now have a '94 MX5
    with the 1800.  The 1800 had noticable changes in the suspension.  The
    94 Mazda is VERY forgiving if you err, the 90 Mazda certainly more
    forgiving than the Toyota MR2.  If you come into the turn too hot in
    Mr. 2, you better know some tricks.
    
    Bob
    

    Interesting bit on Watchdog the other night regarding cats.
    
    Apparently a very high percentage of new cars are failing the first MoT
    with defective catalytic converters and are costing 300 to 1000 pounds
    to replace. This is such a problem that the ministry of transport has
    put this part of the test on hold.
    
    Has anyone had personal experience of this and can you not opt to just 
    do without a cat if it fails the MoT ?
    
    Royston
    

    There's a big article on this in the motoring section of last week's
    Saturday Telegraph. Also, "Honest John" on the back page has been
    inviting letters from readers whose cars are affected by this, with a
    view to compiling data. Nothing on the ET yet, but I expect there will
    be.
    
    Laurie.

    	I'll put this in here, please shift this reply if appropriate.
    
    	Triggered by .59 and ecological thoughts, has any research been
    carried out into the effects of H2S on human beings?  Is it completely
    harmless?  I remember when I was at school (HOW does he remember THAT
    far back!?!) we used to sniff at bad egg gas as we used to call it, but
    no-one said anything about any adverse effects on us, but then they
    didn't say anything about adverse effects from "heavy water" as it was
    called - CTC, nor was anything said about mercury!!!!
    
    				Malcolm.

    re .60 > Nothing on the ET yet
    
    Laurie, could you post an update here if you find anything of interest
    
    Thx
    
    Royston

    Re: .61
    
    H2S is:
    
    i)   highly toxic (more than hydrogen cyanide)
    ii)  flammable
    iii) mildly corrosive, particularly when wet
    
    Other than that there seems little wrong with H2S ! :)
    
    Brian
    

    
    I thought one of the interesting facts that came to light in the
    Watchdog report was that some manufacturers had supplied incorrect
    emissions data to the D.O.T. and that this was causing cars to fail.
    This is the reason the test has been suspended. People were fitting
    new cats who probably didn't need them!
    
    Richard.

                     <<< Note 1343.63 by MUGGER::HESLOP >>>
    
    >>>Re: .61
    
    >>>H2S is:
    
    >>>i)   highly toxic (more than hydrogen cyanide)
    >>>ii)  flammable
    >>>iii) mildly corrosive, particularly when wet
       
    	Oh good, nothing REALLY serious then, just like the Benzene to
    which we are all subjected if we use or even live near the roads! 
    Thank goodness Cats are a rarity on Diesels so far.
    
    				Malcolm.

RE:       <<< Note 1343.62 by COMICS::SHELLEY "Don't get mad, get even." >>>

>>    Laurie, could you post an update here if you find anything of interest
    
    Certainly, no problem.
    
    Laurie.

    Whilst H2S is indeed toxic, it is also very remarkably smelly; you can
    smell it when the concentration is several orders of magnitude less
    than potentially toxic levels. Probably in the Guinnes Book of Records
    for its smelliness.

For smelliness, the record holder is the compound that British Gas put in the
mains gas supply (north sea gas is odourless). This is methy mercaptan, and is
so smelly that British Gas only use a few kilos of the stuff every year !

Dave

    Whats the deal if you don't want your cat replaced if its found to be
    at fault. Are you legally obliged to get it replaced to get an MoT or
    do you need a completely diffrent exhaust, engine retune etc. ?
    
    Royston

    RE .68
    
    If Helium was smelly they could use that instead and then would use a
    negative amount per year.
    
    Graham

    re.69
    	As far as I know, if your car had a Cat. as new, then it will be
    required to be in good working order for an MOT.  I get the impression
    that Cats either work or they don't, if you see what I mean.  Isn't
    some question over the MOT testing of Cats, that the procedure may be
    wrong and failing some "prematurely?"
    
    <<< Note 1343.70 by MUGGER::GRAHAM "Graham Smith, Solution Support Group" >>>
       
    >>>If Helium was smelly they could use that instead and then would use a
    >>>negative amount per year.
    
    >>>Graham
        
    	Que?
    				Malcolm.

    re .70 Malcolm, I think it was humour, you know Helium lighter than
    air, therefore negative amount. Wrong but humour nonetheless.
    
    CATs if fitted must work, or possibly the emissions must be within the
    original values, these can only be achieved with working CATs. I think
    there is some doubt about the emission level data supplied by some
    manufacturers so certain cars are presently exempt.
    
    CATs are not "on or off" inherently, however that tends to be how they
    fail. They fail either because the delicate honeycomb collapses,
    claimed to be due to going over too many speed bumps, but generally
    mechanical damage, this is almost always total failure, simply because
    the gases now find an easy way through. The other way is poisoning of
    the surface, eg leaded petrol - now unlikely, or neat petrol flooding
    the CAT after tow starting. This could poison only part of the surface
    but in practice would probably stop all of it.
    
    Andrew