mlaird

Here's an interesting one:

I took my 8 to my local dealer to have the recall work done, and asked if the recall work might address an occasional rough idle problem I've noticed. Basically, when the car is cold, the engine misses a bit, but I figured that's not too surprising, and wasn't concerned about it. But every once in a great while, I've noticed that even with the engine warm the idle speed would drop down a little bit as the engine stuttered and missed just a little. This wasn't anything that seemed that serious, but I hoped that the new flash would address it.

I figured that the service guy would say that the recall might help, since it replaces the leading spark plugs, and that if I noticed the problem continuing to let them know. Instead, the service advisor guy tried to explain to me how that the rotary engine is "designed" to miss on "every third revolution." He said that two of the rotor faces fire, but the third one is designed to miss at idle, and mentioned something about exhaust gas recirculation.

I tried not to be too rude as I listened in disbelief! Not only does this sound implausible, it also can't possibly cause the type of issue I was noticing. I was feeling a misfire perhaps a couple times a minute at worst, not once every third revolution. If you assume that I'm idling at 900 rpm, then each rotor is firing 900 times a minute, or 15 times a second across the two rotors. His story, if true, would mean that his "misfire" would be occuring 10 times a second, not the stumble here and there over the course of a minute that I noticed.

So my question for you rotary experts out there: does his story have any basis in fact? It sounds to me like a line to placate owners who don't understand engines, not something real. Or if it does have some basis in reality, it sounds like it has been simplified or distorted into a version that doesn't make sense.

I realize that the rotary may tend to miss more at idle than a piston engine since it seems to run awfully rich. But is there anything in the ECU that actually is designed to skip firing one face of the rotor under any conditions? I find that hard to believe.

maxxdamigz

iTrader: (1)

I have never heard of that. The only time I have heard of an intensional skip in idle is on cars that are dumping fuel into the exhaust to keep the turbo spooled at low throttle/idle. My car more or less purrs. Then again, some of the newer piston engines can shut off cylinders to save gas. I did a quick search on the boards and didn't see anything related. I would say that your stuttering idle is completely unrelated.

dmc27

He sounds like a peach.

The renesis only has 2 rotors.

EDIT: Just re-reading that & actually seeing the word "faces". Sorry - not enough coffee yet.

maxxdamigz

iTrader: (1)

Each rotor does have 3 faces which carry on sequential combustion cycles. The engine has 6 combustion cycles going on at all times. This is why a 1.3l rotary is probably best analagous to a 2.6l 6 cyl.

h0rde

For what it's worth, my car has had a rough idle since the day I bought her, brand new. It's usually fine when I start it up initially, but after I run it (in any weather) it idles rough from then until I turn it off. I've had two reflashes and neither has gotten rid of it. My car will be going in for recall evaluation in the next few days sometime.

bsteimel

iTrader: (5)

went to NuCar mazda about 2 weeks ago for the major recall, hvac **** TSB, tail light TSB, and the hard starting TSB. Car is a 2004 with 29000 miles. Passed with flying colors the compression reports were great. They replaced the rear tail light, a/c contorl ****, battery, plugs, and starter. I also did the 30,000 mile service. I got a new key, oil plug crush washers, flushed the coolant, replaced interior air filter. I think i payed about 150 for the coolant flush, air filter and new key. They gave me a car for a day, chevy malibu, for free, they didn't have any cx7's available. They didn't wash the car but it was raining that day so i didn't care.

Olorin2

iTrader: (6)

Just wanted to post my experience with the recall. I took the car to Schaefer & Strominger Mazda in Perry Hall. It's the second time I've been there, the first being for the fuel tank recall. In general, the service guy I deal with (Randy) does a good job and he's very attentive. As for the recall work itself, they re-flashed the PCM and replaced the two leading plugs. They also checked the cat and found no problems. I've only driven it from there back to work again -- about 2 miles -- so not a whole lot of opportunity to test drive yet. If I notice a difference later on, I will update here.

I also complained to them about the rusty rear rotors, which I've been meaning to take care of myself. But, since it was in there for the recall, I had them sand, prime and paint the rotors for me free of charge. They did a nice job, painting them with silver hi-temp paint. We'll see if the rust starts coming back soon.

The car was there for 3 days, mostly because their diagnostic computers were down for a day and a half. They offered an Enterprise car rental, which I declined because I have another car I could drive. They never offered a CX-7 as a rental, otherwise I may have taken it. They also did not top off my gas, but I didn't press the issue. I just wanted the car back with the work done. Since Randy kept me informed so well, I have to say it was a pretty good experience, but nothing special.

SilverStreak

Dropped my 8 at Faulkner Mazda in NE Phila on Friday for the recall, slow cranking at initial start up, and a misfire CEL that had gone back off before taking it in, poor heater control settings (either all the way hot or cold, no in between) and state inspection. They gave me a Mazda 6 loaner from Enterprize. Recall checks passed on the CAT, I had replaced the plugs already so they confirmed the proper leading plugs and condition, they reflashed the PCM but no evidence of the CEL when they did the initial check. Got a new battery and a new heater control module under warranty.

Picked the car up Monday evening, it was washed, tires glossed and a full tank. My first experience with Faulkner's service, easy to get an appointment, the service writer listened to my issues and was very competent. Overall, I was very happy with the experience and will very likely use them in the future even though they are a little farther from me than a few others.

dmc27

They certainly went above & beyond if they hit the tires with any product. While my dealer has been good w/all of it, the "cleaning" generally means the dirt is wiped off, and all I have to do is get rid of the resulting dirty rag lines. Never any tire shine . . .

jcataldo

Did the recall @ Tasca in Cranston RI. No problems, plugs and flash. Gave me a rental @ Enterprise. Enterprise was out of cars? Not a problem, i work across the street from the dealership. It was pouring rain, so no wash, no gas. Service guy is good. Overall a painless trip, and the car was done in less than 2 hours. Tasca seems to be a very busy service department, but i would recomend them.

Balthus

I took my 8 into Wellesley Mazda a few days ago for the recall. Staff was nice and service took a few hours.

After I picked it up, it drove fine for the first 5 minutes - then after it was nice and warmed up I noticed that it was really rough around 2k rpm - feels like it's misfiring. It is consistent: in neutral the power curve is nice and smooth except at 2k rpm where it's very rough. Not a big problem for normal driving but REALLY noticable in traffic.

I took it back in 2 days ago - told that it failed a compression test and needed a new coil pack. I was told it was "just a coincidence" that it happened the same time as the recall work was done (WTF?)

I picked it up last night and even though they did a road test, 5 minutes into my drive home it started again. I'm very frustrated. I plan on taking it back today.

Spin9k

You know what happens when you 'assume'...... A short rotary engine lesson mlaird... their are 2 rotors, each rotates around the eccentric shaft which is analogus to a crankshaft. However, the eccentric shaft rotates at 3x the rotational speed of a rotor. That is, if you see 900 rpm on your tach, a rotor is at 300rpm or 5 rps. So 9000rpm is only 3000rpm for a rotor.

nice animation of rotary: http://www.rotaryengineillustrated.c...imation-6.html

eccentric shaft operation: http://www.rotaryengineillustrated.c...ession-ex.html

Hope that helps.

mlaird

True, but each rotor fires 3 times per revolution. So at 900 rpm on the tach, it is true that each rotor is spinning at 300 rpm. But it is also true that each rotor is firing 900 times per minute, or 15 times a second.

So I still stand by my disbelief in the service guy's comments. If true, the engine would be misfiring "intentionally" 10 times per second (five per rotor). I would expect that we would all feel that. And besides, my original question was about an apparent misfire a few times a minute, not a few times a second.

I'd still like to know if he was completely all wet, or just giving a bad explanation of a real phenomenon. Maybe I need to bug Rotary God or someone like him who knows more than that service guy ever will !

Spin9k

Never heard of the 'intentional misfire' idea. Sure sounds like BS, at idle the plug firing is reversed, but as far as I know all faces fire, I mean emissions would go to hell if they intentionally misfired.

I'd be concerned with coil misfiring.

VOODOO8

My 04 is in with Werner Mazda in Manch-Vegas, NH for tranny work so I had them do the recall as well. I'm on my second engine, about 18K miles on it, and have started having some fall off in top end performance on the replacement (same way the original motor first started to show signs of failure). As such, I asked that they perform the entire set of recall tests and brought the printed TSB's in with me to confirm with them what this meant. Result of diagnosis was new coil packs as well. Knowing from posts of other fine citizens of this site that there was a new version of the coil packs in circulation with Mazda I confirmed that the part number for these replacements was N3H1-18-100A-9U. I don't know what the outcome will be as I have yet to receive my vehicle back (3 weeks and counting - additional bearings replacements found after they got the tranny disassembled on the bench), but I would much appreciate learning if the coil packs you got were the same part number as I have noted above.

Thanks!

BLACKOUT

Falkner MAZDA NE PHILLY

I have gone there to everything from the dreaded tail-lights to the recalls, broken visor that split in the rear to a lightbulb burning a hole in the bottom of my door panel and even the most recent being the recall on the E-BRAKE boot binding and Breaking off in cases like mine and you know they have always Done there best by me and never given me a single sign of grief. The man in service to talk to is Todd McNinney
And the young kid in parts will hook you up if you are Worthy.

KiwiRX8

Finally writing in...
Took mine into Modern Mazda in Torrington CT for the recall early December. This is the dealer I got the car from and service has been stellar all along.
Do the usual paperwork etc as I was also getting them to fit the snows at the same time. They hand me the keys to a very nice shiny CX-7 and tell me to have fun. I liked it other than the turbo lag/jolt when you start from a complete stop.
Get the call later that day that all is ready to go and come in whenever I am ready. Get there after work, my baby is sitting in the front looking very shiny. They cleaned it inside and out and gave me a full tank of gas. I had less than 1/4 tank when I took it in as I had purposely ran it down.
So top marks to Modern Mazda. I had never heard of them before I got the RX-8 and was originally looking at another dealer in Danbury until a friend recommended these guys.

tmak26b

When I did the recall, no spark plugs, no vacuum, no full tank