Mystery - 09 RX-8 sport manual - past month and a half roughly since I shut off AC coz the weather has cooled, whenever I am stationary in neutral (totally regardless of surrounding traffic) or reversing, I am smelling what seems plainly to me (and my wife) quite a strong exhaust fumes smell in the cabin. No sign of it when traveling forwards at any speed. Typically on external air feed rather than recirculation.

Worried about possible CO implications, I asked the local dealer to check the length of the exhaust system at the latest service last week but they say they found absolutely nothing wrong and could not replicate the fumes smell in the cabin either. Thinking their mechanics are just around too many cars and can't smell anything anymore, I wrote to Mazda and they are pondering their response. However, also I ordered a couple of those CO Detector cards and placed one in the vehicle. And so far absolutely nothing, the indicator hasn't grayed even a fraction, suggesting indeed there is no Carbon monoxide. And yet when stopped or reversing I can smell exhaust, as if I'm always pulled up behind some old 70's Chevy thats belching crap out the rear.

Two questions then :
(1) Any theories on what the heck could be going on here? aside from wife and I going stark raving mad?
(2) Even if no CO (which of course is odorless anyway), is there anything else in exhaust fumes (if thats what it is) that can be dangerous to health?

Thanks for any input.

Mike
NC

 

Cat might be failing, mine started to smell right before it blew out, literally.

 

Nice one

 

Going catless improves my health.





Yes, your cat is likely failing since you didn't mention any changes in exhaust noise (which would be due to an exhaust leak, the other way you can smell the exhaust fumes more clearly). And please don't just "bring it to a dealer to have them check". They will just plug in an ODB2 reader, see that there isn't any codes, and say "nope, working fine!" Our ECU doesn't detect cat failure unless it's missing (but then only part of the time), or so far clogged that it is starting a fire under your car.

 

Thanks for replies. I then pitched the failing Cat idea at Mazda/dealership and the latter has already replied early this morning that the car was fitted with a new Catalytic just before I bought it, about 1500 miles ago so I guess not that either. One thought, I don't drive it very often (couple times a week) and read that these engines need quite a frequent work-out. Could the lack of activity contribute to some kind of gunky build up somewhere that is impeding proper venting etc. In other words do I just need to take it for a longer journey and spin the revs quite a lot?

 

Certainly. Regardless of what the current issue is, take it out and give it a good wankle spanking, full throttle all the way to redline (1st or 2nd are within legal speed limits, 3rd+ are not, so keep that in mind and be smart about it if you pick something higher than 2nd). You should notice it smoothing out as you burn out/off that junk.

 

Did you check the cabin air filter?

 

if the exhaust system was worked on just before you purchased it , it is possible something wasnt connected correctly allowing for an exhaust leak.

 

Exhaust leak is my guess too.

 

Mazda USA has largely opted to dodge the issue and stand on the sidelines while the dealer insists theres nothing wrong with the exhaust based on their recent evaluation but that my heat shield is coming apart and some backing material may be melting and causing the smell, thus $250 please Sir for a replacement. However, what I can smell isn't a burning smell at all, its the exact smell you get if you stand behind the car while its running and take a big inhale.

Guess I'll have to get an independent shop I usually use for other car work to just hoist the thing and give me a second opinion.

Again, appreciate the views offered.

 

I hate to point out the obvious, but it still might be your catalytic convertor that is the issue.

You indicated that they replaced it, but did they actually resolve the issue with the car that caused the failure of the convertor when they replaced it? That's the question you should be asking.

If the ignition coils, or a spark plug wire went bad, and that eventually lead to the death of the convertor, but all they replaced was the convertor, then you still have the original problem to work out on your car, which would also explain why you are smelling so much exhaust.

If it were my car, that I had just recently bought used, the very first things I would do to it would be to buy a new set of coils, wires, and plugs, and put them in, just so I would know that everything is up to snuff on my car.

I don't know if you've done this already or not, but since you never said how many miles on on your '09, and the '09 and newer cars aren't yet known for killing cats just yet, I would expect there to be some cause for the death of it, and coils, wires and plugs are usually the top suspects.

BC.

 

Sounds about right to me. I just hit 35k miles in my 09 and replaced all those(plugs at 30k) and it is running much better. My car is also dumping out a noticeably smaller amount of gas in the exhaust because there are way fewer pops out of the exhaust now(I have a midpipe). So yea if your coils are bad or wires(even my wires were starting to look bad at 35k miles IMO) you could be doing some major damage to that new cat.

 

Right after you start the car before it gets hot get someone up front to listen under car and in engine bay while putting a towel over exhausts. If not whoosh leak sound then drive around, and heat it up. While it runs stand around the back, and sniff the exhaust. I can't really smell much after the cat is warmed, but when I've just started, and we get right back out to get mail, my wife keeps asking why the gas smell until the cat is lit.

I've got the BHR ign, and I get very good gas mileage 22- 26 on hwy depending on the environment or speed, so I'm not about to play around with the a/f ratio, and there's absolutely no smell when pulling over on hwy.

If you have a cat and the smell isn't better than a dogs breath (ha!) after warmup, then you're cat is kaput.

 

Where to from here? I took the car into the dealership again this morning and had their RX8 tech and Service director check the cabin smell with me. They both insisted it was par for the course RX8 smell, citing deliberate oil burning aspects of the engine etc. However this exhaust fumey smell wasn't apparent in the Apr-Sep period after I first bought it (09 Sport 41.5K miles). They pulled a 2011 model into the shop for comparison and ironically the 'sniff compare' test backfired on them as far as I was concerned because the '11 car smelled fine but they still gave no acknowledgment that there was any difference to their noses! So what can I do? The next nearest Mazda dealer is 45 miles owned by the same people and beyond that I'm guessing 100 miles, which I can't reach during weekday service hours due to work. My local repair shop didn't want to check it as they're not comfortable with the rotary engine. I've got the cabin blower switched off at this point but some air movement would be nice. Seriously if sadly pondering dumping the thing, probably losing a chunk of change for 8 months of ownership and being the hell outta RX8's as I'm not sure what to do to get Mazda interested in the matter.

 

I had a similar Issue, but it turned out to be a leakng fuel rail... are you sure it is exhaust you smell? makr sure it is not fuel vapor (i suspect mine was broken by a ham-fisted technician replacing the sparkplugs)

My fuel rail was replaced under warranty, & they were quick to service it (liability ftom the fire hazzard & all)

 

Okay, there's your proof.

You have over 41k miles on your '09 RX-8.

Go buy a new set of ignition coils, spark plugs, and spark plug wires, and tell us if that improves things. If you have a spark tester, you can even test the coils to see how good/bad they are firing currently before you plop down the money on new coils.

If you want to before you do that, and you have a set of ramps or stands and a jack, and some tools, you could get under your car when you have some time, pop off the convertor, and take a look to see if its dead already from your plugs and wires being dead after the install of the new convertor.

Anyway, it sounds like your coils are getting weak, like I had mentioned in my previous post. You might want to fix those before you cause yourself some un-needed long term grief.

BC.

 

Okay Blade, can I ask you this; since I'm about as mechanically minded as an ardvark (and thats probably insulting most ardvarks), could some relatively budget friendly tests (cat check, coils check etc) be conducted by say a Precision Auto Tune or even a Meineke type place before buying new coils, plugs etc, which can run a fair penny or two? Supposedly, plugs were replaced around 39.5K and coils checked out okay at that time before I bought the car according to the dealership but my faith in anything they say is running very low now. Could one of the above shops perform the necessary checks or are they too generic for an RX8 and do I need to find a more specialized repair shop?

 

Yea (again) I would start there as well.

Techcom7 the problem everyone is having here is that they are trying to get you to check things yourself, and you are just taking it into the dealership. There is only so much that can be done at the dealer without a cel or absolute proof something is wrong. If you yourself are not willing to check under your car then try and find a friend or family member that will and check stuff out under there. Sure maybe your car had a brand new cat 1500 miles before you bought it, but what happened in those 1500 miles is anyones guess.

Ask that independent shop you keep mentioning to put it on the lift and at the very least check the cat. You said they are not comfortable with the rotary, but I don't see how that has a thing to do with dropping a cat and looking at it. All cars have a cat on them stock, so being mechanics I would hope they have at least a clue about them.



Edit: Just saw your new post. Go with a shop you TRUST, but yes technically a meineke should be able to do it. Personally I steer clear of all meinekes and jiffy lubes, anything like that. Try posting in your regional forums and see if anyone has a good mechanic they like and trust. Be sure to mention it does not have to be rotary specific when you post.

 

If you lived in the Colorado/Denver/Boulder area, I would just say bring it over to my house, and we'll take a look at it, but I don't know where you live.

If you let us know, someone who's reading this might say to bring it by their place, just cause we're occasionally known to like to solve puzzles.

But yeah, don't worry about insulting aardvarks on here.
Some of the people on the forum are in the same boat you are, and don't know the difference between an oil dipstick, and an ignition key.

You might want to ask the local forum for your area if they can recommend a good shop, as I would trust forum members more than a random chain exhaust shop to give me an honest opinion.

BC.

 

okay, does anyone know a good repair shop for RX8's in the Wilmington, NC area?

Meanwhile thanks for suggestions provided.

Mike

 

So took the car to a different shop that fixes performance cars and knows RX8's. And the guy there has 30 years experience and he took a few sniffs and... and... he thinks it smells like the Cat!

So now its back to Mazda to ask for the Field Rep to come out and I'm getting to the point where I hope the Field Rep brings an f...ing Field Gun and one '09 rx8 could be toast. Anyway, the saga progresses, maybe the Field rep won't have cotton wool stuffed up his nostrils like all the dealership workers seem to.

I know this next remark will draw abuse but I'm starting to hanker for my '97 Supra turbo, pretty much the end of the production run, had it five years, oil changes all it ever needed, never an issue, stickered at $39K and I sold it for $33K (buyer drove nearly 1000 miles each way to get it) so barely over $1K depreciation per year. But it did have a silly tall fin on the back.