Mr. Pockets

Here's a new symptom. I've taken the car on quick trips up and down the freeway twice today, just so I can accelerate up through the rev range a couple times in second gear.

Each time I did this today, at least once at WOT I've had a moment of hesitation from the car, then a hissing noise, clanking as I hear bits go through the exhaust, and finally a thin grey cloud and chunks - chunks I can see bouncing down the onramp - are expelled from the exhaust.

It did this before for awhile after I replaced the coils last time I had a bad misfire like this. It's been fine for a few months. At the time I figured the bad ignition parts caused the misfire and therefore damaged the cat. I wonder if it wasn't just the cat all along.

zoom44

big chunksa cat were also not mentioned previously

the engine trouble smoke happened at an autocross(which you didnt mention previously either )

so there have been chunks of material fly out of your exhaust on multiple occasions and the cat hasnt been physically inspected or replaced yet?

you did an autcross knowing you previously had chunks of catakyst flying out of your exhaust?

what modifications have you done to your car?

have you ever cleared the nvram with the 20 brakestomp clear? please have this sensor and its harness checked

https://www.rx8club.com/showthread.p...or#post2971610

Mr. Pockets

Look, I'm sorry, but this has been going on for quite some time. Excuse me for not mentioning every little thing the car has done over the past six months. It's been a long, frustrating period. I find my seat warmers insufficient in very cold weather and my instrument cluster rattles. Better?

I have not modified the engine at all. It is on the stock intake with a K&N panel filter, and I have a Greddy cat-back exhaust on the car.

I'm going to drop the car off at the dealer in the morning to have them look at the cat and, hopefully, order me a new one.

I have owned, and worked on, a lot of cars and I have never had a problem with a catalytic converter. This is all very odd to me, and it seems to be a chicken-and-egg situation. I don't know which came first, the misfire or the bad cat.

I replaced the plug wires tonight. I had a new set I just hadn't gotten around to installing. In order to get to the coils, I removed the box that's attached to the side of the flexible intake tubing. It had a couple ounces of oil in it. I pulled off a couple of the vacuum hoses, and they were coated on the inside with oil. I have no idea how it got there, but that seems like kind of a lot.

While replacing the wires, I checked the rear leading plug, because it was easy to get to. It had brown crust on about 50% of it. I have ordered a new set just in case. I replaced these plugs only a few thousand miles ago, but both misfiring incidents occurred since then.

zoom44

oil in the intake. you can get a kit from mazda to rework the venting to alleviate that. it may be under warranty. or you could install a catch can. it can get there from over filling and also from just topping off the oil and some "spilling" into the vent on the filler neck.


http://www.finishlineperformance.com...50-06-1664.pdf

btw oil in the intake can cause bad maf readings which can make car run even richer than normal causing fouled plugs and misfires and lead to premature cat failure due to over temp situ caused by unburned fuel reaching the cat and igniting in it.

cat failure can be more common on a rotary than a piston engine because of higher normal egt's. so what is a small amount of higher egt in a boinger caused by the above scenario is enough to push the cat over the edge with a wankel.

Mr. Pockets

I dropped off the car this morning, and the dealer claims the cat is fine. They ran a 'catalyst efficiency test' on it, and that told them it was okay. I asked them to remove the cat and actually inspect it, which they said they'd charge me for. I agreed, and they still claim it's fine.

I have no idea what to do about that. I do not think the cat is fine. The chunks that came out of my exhaust came from somewhere. The cat also rattles now, where it didn't before. The dealer agrees with me that the cat is what's rattling, but they still won't replace it.

I suppose my only course of action is to keep provoking it and see if I can get it to show more symptoms.

Razz1

There's your problem. Zoom44 told you.

Put a filter on the oil spout. cap off the intake. Clean all the hoses and intake tube, clean MAF, install new plug as as they are fouled.

Seats, warmer is normal.

Dash rattling has been traced to small sand stones wedged between the steering column and dash. Can't get rid of the rattle if you have a KN intake. (You have filter so thats ok).

Also, KN filter has spray oil, get air compressor clean excess oil on filter. Many get oil from KN filter on MAF causing MAF and CAT problems.

Good Luck on the CAT, they are trying to save money. It passes test and works but is falling apart.

StealthTL

iTrader: (1)

The cat inside is in two pieces - the first, the one you see when you look in, is about four inches long, then after the O2 sensor hole there is a second layer, about eight inches long. This second piece could be destroyed, and rattling around in the muffler, the cat efficiency test would still be fine.....

philipchan

I had the same situation before(miss fire, and engine light on sometimes), it was solved after spark plugs replaced

kersh4w

iTrader: (3)

congrats on your new catless midpipe.

nycgps

iTrader: (1)

can u go another dealership ?

swoope

iTrader: (5)

call the mazda 800 # and explain the what happened. they will call the service manager and it should go better from that point.

if not escalate it with mazda na on the phone. ask for the area rep..

if the dealer said they did a visual inspection and you did not get a look, or no photos. with the stuff you have described, sucks to be them..

beers

Mr. Pockets

To be fair, the service writer offered to show me the cat if I came to the shop to see it. Unfortunately, they had my car at the time.

Of course, it would make sense that I would have to be there to press the issue - I've had to hold their hands every step of the way so far.

Their service manager is supposed to call me when he gets back in to work Monday. If I can't convince him to replace the cat, then I'll escalate it up through Mazda NA. He seemed like a pretty reasonable guy, so we'll see.

brillo

I've run royal purple 10W30 for 5 years in my car and never had an issue. I also get ~17mpg in the city and ~24 hwy and I don't baby the car.

I suggest a different dealer who isn't an idiot.

Mr. Pockets

Update:

The service manager has had my car, driving it as his own, since Monday. He has seen no problems with it in that time. This does not surprise me. It goes months in between misfiring and the exhaust had stopped spitting out chunks before I dropped it off. Of course.

They were able to find one Mazda service bulletin that recommends against using synthetic engine oil. The bulletin is for hard starting. I will post the bulletin number later; they're providing me with a copy.

Sigh.

When I pick it up after work, I will change the plugs. I just replaced them a couple thousand miles ago, but they're very crusty already. The car acts like it did before I replaced the plugs last time. It's just not quite as smooth.

I will also clean the oil out of the intake tract. I bought a can of MAF cleaner to use...on the MAF.

I have an oil catch can on its way. Maybe the misfire was caused by excess oil being ingested by the engine via the intake. I dunno. The can should get here tomorrow, so I'll have time to put it in and...zip-tie it to something, I guess.

We have another event Saturday. Here's hoping it doesn't act up again.

Mr. Pockets

I believe I have found the source of my misfiring problems. After getting the car back from the dealer a couple days ago, I replaced the plugs. I had pulled one over the weekend, and it was pretty well fouled.

When pulling the plugs, I found that they weren't in the right places. Over the winter, because it was cold out, I had paid a local shop to put a new set in. I was very specific and told them that they had to go in the right places. Apparently they didn't listen, because one rotor had both trailing plugs and the other had both leading.

If you want something done, do it yourself.

It's running a heck of a lot smoother now through the rev range, which is pretty typical for having a new set of plugs in. We'll see, I guess.

I still have an oil catch can on the way. Hopefully that'll keep all the oil out of the intake tract.

StealthTL

iTrader: (1)

I still think it's that evil synthoil.......

nycgps

iTrader: (1)

The sky is falling.

Razz1

Can you please contact the dealer and thank them for their help. You don't have to tell them what you found out. However, admiting that they were correct will go a long way in the future should you need their service.

I examined the ingredients on the MAF cleaner verses brake cleaner. Same except MAF ensures that is is safe for plastic while brake cleaner says safe on most plastic, do a test. Therefore difference in quantity of chemicals.

Mr. Pockets

I appreciate the sentiment. I left things just fine with the dealer. I know the service manager from his days at another dealer, and we get along just fine. I would like to tell them what I found, but I worry it would give them an out if the engine needs to be replaced under warranty in the future.

As for them being 'right,' I don't see how they were. They refused to believe me about the cat spitting out pieces. I still think that's a problem and it'll have to be replaced some day. They also never even looked at the plugs, obviously. I brought it to them to figure out (four times), I told them I had the plugs replaced over the winter, and they didn't think they should look at those.

They were also adamant that the problem was synthetic oil when an obvious problem was staring them in the face.

The service manager has admitted to being rotary ignorant. He literally knows less about the engine than I do, and I don't know a lot. They're nice guys, really, but without a website or a diagnostic machine telling them what to do, they seem to be lost.

As for the MAF cleaner, it smells exactly like brake cleaner. It eats oils and other contaminants much the same way, too. Neat stuff, and I'm sure entirely healthy to breathe. :p My MAF and entire intake were just dripping with oil. It was pooling. I have no idea where it came from, but I'm keeping my eye on it.

04RX8man

well the oil in ur intake is from it venting from the oil filler tube through the hose into ur intake....catch can will take care of all that!

ronx8

+1. seemed like the dealer actually cared. wow.

shazy

Hmm... maybe I should get a catch can as well.

Anyway, atleast you finally found your problems

Good Luck.

Mr. Pockets

Sure, the service manager tried. He really did. But it's pretty clear to me at this point that they don't know the car very well and if the answer isn't on a screen in front of them they don't know what to do.

Again, I like the service manager at the dealer. He's a good guy. But they should have found this problem. I see no reason to tell them that 'they were right.' They missed a very obvious problem with my car and refused to believe me when I said the exhaust was coughing up chunks of cat.