bhop

Well, if anyone was worried about the CEL, everyone here should know why it would stay on. Also, one ROTOR? Stop driving the car and take the bus. If a any mechanic cannot find the problem then................. maybe new engine lol.

Even if your car was healthy in the first place and you had replaced the stock parts with aftermarket parts, your CEL could still come on right then and there or could have eventually came on later. I added the racing beat midpipe and my CEL stays on but before that all I ever needed were new coils and plugs but even then my CEL never came on. Some of the smells could be from your aftermarket catalytic converter. I have about 90,000+ miles on now and still running strong with no issues. Also, keep in mind that you need to go to different mazda dealerships, some are better than others at finding problems.

zoom44

you bought the car used with these after market exhaust parts on it? or you put these parts on? Im having trouble understanding since you say you dont know the brand of the cat.

zoom44

oh where do you live- yes its important for us to know the area you live in- and how was this "one rotor" issue resolved?

xalaskan

Bought my 2005 1.3 Shinka about a year and a half ago. Love this ride. (didn't think anything would top the Spyder) Any ways, last winter I got a CEL. Put the reader on it and it threw a 420. Asked around and the most popular opinion was a bad cat. Found that really hard to accept at 53K miles. In the coming months I replaced: plugs, wires and ignition coils. Significantly more power like didn't have to downshift to 5th when going up the same hills I went up before! It took about two weeks before the light came back again. Car ran just fine with no issues. Then at just over 59K I started noticing a bad odor from the exhaust. Smelled a car that was running rich with a burned fuel smell. There's a little gray smoke but you have to look hard to see it. I finally broke down at 61K and bought a replacement cat unit from Amazon. It's more like an exhaust extension but it's called a cat. Took it to my local mechanic as I just couldn't get under it enough to change it. At the same time I had ordered the lower O2 sensor. He got them replaced (charged me $50 to do it), nice. He told me the old cat and pipe weighed a lot and agreed the cat was plugged. Definitely more power than I've ever had with this car. That said, the odor is still there with a CEL. He said he tried a couple of adjustments for intake but to no avail. Really hate to take it to the dealer. The issue reminds me of an EGR valve issue but looking at this mess I'm lost. That's my story. I went through the new user forum and don't see any thing that jumps out. Any ideas that I can try before doing the dealer option????

wcs

iTrader: (2)

A perfectly operating factory catalytic weighs a frigging tonne.
They are heavy bastards period.
Most aftermarket cat IMO are ok but most can't get rid of the smell and may not pass a smog test or have a very long life.
If you use a cat -delete pipe .. WOW the car really stinks or smells awesome if you love unburnt hydrocarbons like I do!

Catalytic failure is common on these cars, very common.

So the cel is likley P420 Catalytic efficiency below threshold, you should get it checked to be sure.
The smell is to be expected.

Don't want to worry you but driving around with a failed cat can lead to premature engine failure.
Look around the forum. Enjoy

Edit:
OH I would love to know what the "adjustments to the intake" were by the mechanic

RX8Soldier

iTrader: (24)

So your saying that your car even told you that the cat was clogged (p0420), and you ignored it because the mileage, then drove it anyways, and now your finding out that the cat was indeed clogged and it's causing you pain and misery?

This is what happens when you don't listen to needy bitches (the rx8).

You replaced ignition components, sure. But driving around with a fouled cat can cause bad stuff to happen in your engine, and your new ignition may be toast now (because it had to work harder).

Yes, it could be the new pipe you have that's causing the rich smell. But you could have unburnt fuel getting thrown into your pipes because, with the afore mentioned, you ignition is dickered.

Get those checked.

Second, this "exhaust extension" could also be dickered because it can't handle the high exhaust temps of the renesis, destroying or clogging it.

Get that checked.

Report back

xalaskan

I originally posted to those needy bitches posting the question about that cat asking is 55K about right for a cat. All I got back was cat. You need to understand something, dickering with cars for over 30 years, 55K doesn't seem right for a cat change. The beginners forum showed that the RX does go through cats but doesn't say the mileage range to expect this. Had someone said something other than cat and answered the question, then we're good. When I read about the cats going bad I'm thinking maybe 90-100K. I've had cars that went 200K without a cat change. I've replaced these before as well as done other work.
That said, the miles driven on the car since is minimal but the issue remains about the strong exhaust smell that started before the cat replacement and didn't go away. I was able to find out that the mechanic who was playing with this (backwoods guy) was trying to adjust airflow rates at the intake? That's a new one on me but without a good manual I have to go with what I'm told. As previously describes, if this was a late 70's or 80's car it reminds me of an EGR valve not opening re-burning exhaust gases. I don't see anything but who the hell knows what it would look like or what it may have been replaced by. I was hoping someone else has had this issue. The exhaust used to be clean burning but something prior cat started to go bad.

wcs

iTrader: (2)

Your posts are a little hard to read.

Other than the smell and the CEL the car is running ok?

xalaskan

Car runs great but that code is preventing it from passing inspection. Recap, at about 53K CEL came on with 420 code. Suggestions came in to replace the cat and change out plugs, wires and ignition coils. I went with the ignition parts. Performance picked up and code reset by me. About two weeks later that same code came back. About roughly 3-4K miles later a strong emission odor started up smelling like burned fuel. The odor got stronger. I was thinking that the cat must not be burning the residual exhaust gases. About 3-4K miles later I opted to change that cat and lower O2 sensor for the heck of it. The cat and sensor didn't get rid of the exhaust odor or 420 code. I've had older vehicles that had EGR valves that stuck and wouldn't open and got similar odors. The local backwoods mechanic was making some kind of intake airflow adjustments but don't know exactly what. He couldn't get the issue cleared. Before I run to the dealer, I thought perhaps someone else has had the same exhaust issues? Thanks

wcs

iTrader: (2)

Series 1 has no EGR so at least we have that out of the way.

Like I said before. Aftermarket catalytic's IMO are not as good as the OEM for emission control.

I don't know anything about those O2 foolers other than what I've read on this forum, but it would seem that most of them don't work.
If you can't pass the emission test .. you need a better catalytic.
OEM is your best bet.

xalaskan

Thanks for the input but the question still remains, the odor was there for a few thousand miles before that cat change and was still there after the change. That tells me something started going wrong prior to the catalytic converter replacement. I've read threads here where some folks actually gutted their units and don't get CEL's? When I said EGR, it just reminds me of something I've experienced in the past with older vehicles. I suspected something took its place but with a rotary engine, who knows. Just was wondering if there was some kind of sensor or something I could check with a meter, a hose or line somewhere, etc.

TeamRX8

iTrader: (25)

Does your reader display AFR or Lambda from the O2 sensor? Because this is how you tell if it's running rich or not. If you have perfect AFR/Lambda readings (neither too rich or too lean) it will still smell "rich" if the cat converter isn't working. That's why you can't judge it by smell.

The rotary exhaust runs much hotter than a piston engine. As such it requires a special cat converter. . Idling and cruising it's not uncommon for the rear O2 sensor to readout 1650*F exhaust temp. A piston engine cat won't live long at that temp.

However, I think you need to post up a link to what you bought. It seems to me you're confused about what it is you really bought or maybe how effective it may be.

xalaskan

Unfortunately it doesn't. I bought a unit from Amazon for about $250 after reading reviews from other buyers. All had no issues other than a couple installation complaints. I was thinking if I'm going to go through one of these every 50K, why go top dollar. So I had the problem before buying the unit and still have the issue? I've read posts here about people gutting their units without getting CEL's. That's why I thought low end units will be just fine? Looks like I'm heading to a dealer.

TeamRX8

iTrader: (25)

If you really want help then please post the link to it

Loki

iTrader: (1)

Do you have an OBD reader? Team is right, the cat might be fine and you're just running rich. Or the cat is not fine, you need to narrow it down. If the AFR reading via OBD is 14.7-14.9 at warm idle, and it smells rich, it's the cat. If the reading is above 14 and your short term and long term fuel trims are not near 0, then whatever your backwoods mechanic did to the airflow sensor is playing into this.

Can you clarify what he did, at least? There is no good reason to mess with the airflow sensor input at all.

RX8NOOB2024

Hi Everyone, I recently bought a 2007 RX8 with 158,000km and I've been having this issue of the car dumping fuel, but the car runs smooth no burning oil and it runs like a clock. I can't figure our why it's
burning so much fuel. Every time I come to a stop I can smell the burnt fuel in the cabin. Has anyone had a problem like this before??

Loki

iTrader: (1)

It should definitely be burning oil, there's an oil injection system for this. How familiar are you with rotaries? I'd suggest reading all of rx8help.com to get up to speed.
As for fuel consumption: poor ignition due to dying ignition coils is one common issue. Coils start to be a risk beyond 45,000km, change them preventively. There are no symptoms, it'll still run fine with a dead coil, depending on which one it is. The other thing is catalytic converter getting clogger (usually due to poor ignition). Both of these issues will kill your engine if allowed to continue.

IS the check engine light on and are there any codes?
Where are you located?

RX8NOOB2024

I'm located in Vancouver Canada
Check Engine light is present (Code Reading) Catalyst System Efficiency Below Threshold Bank 1
I took it to a mechanic and he said it's O2 Sensor, so I replaced the O2 sensor and the check engine light went off for a day and then it came back on.
I have owned an RX8 a while back. I haven't experienced anything like this before that's why I'm asking the experts.

Loki

iTrader: (1)

Ah. Never go back to that mechanic again. Sounds like you need a new cat, or at least to have a look inside your cat to evaluate it. Is there any reason to believe the previous owner gutted the cat and what you're smelling isn't so much rich as untreated exhaust?

What kind of fiel mileage are you getting in L/100km?

RX8NOOB2024

Currently, I am averaging about 22L/100KM.

I've only owned the car for a few months. I asked another mechanic, and they stated it could be a cat.

Is it possible that it is more serious than a cat?

The car runs extremely smoothly, and I phoned a rotary shop near me, who stated it shouldn't be running smooth if it's the cat is bad, and that if I fail to address the issue correctly, my car could catch fire.

Loki

iTrader: (1)

Jesus. It should be half that if there's highway driving involved. Go see the shop, have them diagnose properly. This is beyond troubleshooting by phone.

You could look under the car after a drive and see if the cat is glowing.

Is the car stock?

RX8NOOB2024

Car is stock

I'll check tonight and see if it's glowing.

Thanks for your help. I will update the page once I get an answer from the shop.

RX8NOOB2024

I took the RX8 to a shop near me and they checkout the cat and it turns out there is no cat.

Without a catalytic converter could that alone result in fuel economy of 22L/100km

Loki

iTrader: (1)

No it shouldn't affect fuel economy.
Not sure if you mentioned already, have ignition coils wires and spark plugs been replaced in the last 20k miles? If not, I'd do that. Absence of cat means someone gutted it, potentially because it was clogged due to poor ignition.

RX8NOOB2024

Previous owner stated it was replaced, but now that you said that I will replace them, also there is a ticking out coming from on top of the engine bay.

Could that be related to bad ignition coils / spark plugs?