241Commuter

I'm sure you'll let me know if this is a silly question. I've been reading all the flooding threads and this is clearly much more of an issue than it should be for a $30,000 car. Even guys who know better get sucked in. So... with all the programming that's gone into the car, why doesn't Mazda program a cold shutdown sequence that leans out the F/A to zero until the engine stops? No more flooding...

red_rx8_red_int

You're preaching to the choir. I'm sure we all agree that the flooding issue is the single most annoying downside to the 8. IMHO more than the HP issue. No one that doesn't have an 8 will know to follow this procedure, much less really follow it. I will not valet my car or park in a downtown lot that collects your keys so they can pack the most cars onto a small lot. Even if you explain about the procedure, will they follow it? I don't know of any other car that suffers from this problem. Note, I never owned a deisel. And I can't believe it's not in the manual, it's on some quick read brochure. Did Mazda not know about this til late in the delivery process. Something this important deserves a big red remove by consumer only sticker on the steering wheel as well as a very prominent placement in the manual. That said, I'm the only one that drives the car and instead of letting it idle to warmth, I drive around the block and then pull back in my driveway if I need to do a short move (I don't remember what exactly Mazda calls it). So it comes in handy when my addiction of driving the 8 needs feeding. I pretend to "need" to move the car and once it gets warmed up, I do a couple of WOTs before going home. Very relaxing. My wife doesn't know that half the time I took making sure it was fully warmed was having fun. Maybe that contributes to my low MPG.


On a related note, since there's no other cars that need to be idled to warmth before shutting down, and the 8 is said to get ****-poor mpg at idle (I know all cars get bad mpg at idle, while parked, no miles at all, but the 8 is said to be a real hog at idle), the EPA estimates should be downgraded to include this unusual requirement.

B-Nez

Are you joking? Lean it out to Zero until the engine stops? Do you mean until it stops for good, because that's what you'd end up with eventually. Rotaries are more sensitive to detonation than piston engines.

I mean, I can see where you're going with that, but leaning it out just isn't the right answer. Yes, though, something more automated would be nice.

RX-jimenez

hey i are going to be a rx-8 owner pretty soon, i been notice this flooding issue for quite some time here, and i understand a little but for other that may not can you just explaind with alot of details what you have to do to not have this problem?...thanks...

Astor

It is in the manual

241Commuter

I knew somebody would know why that's a silly idea. I don't know much about what causes a firing chamber to detonate or the kind of damage it could do. There are still opportunities for shutting it down more safely - like automatically reving to 3k for a few seconds to warm the chambers up and then leaning the a/f to a less rich condition before shutdown. Besides throwing less gas in the engine, it would be cool to see the look on the parking valet's face as he freaks out. :D I think the engineers at Mazda could work out the details for something, anything, that's better than what we got now.

MEGAREDS

Not really, Astor. The manual has an "emergency" procedure for starting the car when its flooded (which I recently had to use - see my post: Flooded... Emergency Start Procedure Let Me Down ), and there is a separate "Quick Start" guide that the dealerships give which discusses the "short move" procedure, but they don't join the two together for some reason. I think Mazda struggles with this issue and that might explain why the short-move procedure is not really in the manual.

People are telling me that my tow tomorrow and the de-flooding will be paid by Mazda. If so, they're spending a lot of money on this to keep it a non-issue for their dealers, because I don't see how my failing to follow the short-move procedure is a "materials and workmanship" issue (unlike my November Seat Belt Debacle, which I believe was caused by a non-standard buckle). My sense of it is that there are difficult technical issues here that we're not understanding. Wakeech mentioned that the mounting of the spark plugs on the side of the engine makes them prone to fouling -- that sounds like a plausible theory. I suspect the placement of the plugs is a huge issue, so they needed to put them there, and if they are there, they tend to foul.

No one has more of a right to be pissed off than me at this particular moment in time about the flooding issue. Tomorrow will be my third day without my baby. In my mind, so far anyway, it's not got me too crazy. I'm not real happy about the difficulty of finding a rotary mechanic during a holiday weekend, but I'm not working very much either this week, so it's not particulary fair to be pissed off at people for wanting to take a few days off. I'm fairly sure I could have gotten a loaner car if I had asked for one.

The service guy I spoke to about the car said that he didn't have a Mazda tech available and that the RX-8 was a "specialty vehicle." Yes, I know. In fact, that's really a big reason why I wanted to own it. We'll get it figured out... give it some time. The list of things wrong with this car is really quite short compared to the other list I've got.

rotarygod

The biggest issue is that the trailing spark plugs fire before the leading spark plugs at startup and idle. The trailing spark plugs have a very small hole to fire through and are set back quite far in that hole shrouding the spark pretty heavily. This alone causes the plugs to foul easier than the leading plugs and now we complicate the matter by having them fire first at idle and startup. Also unlike the RX-7's the RX-8 does not use wasted spark mode which fires the leading plugs twice as much. They just need to go back to the old way or spint the engine over faster. Everytime you get in the car press the pedal all the way to the floor (whether flooded or not) and crank it. Let it turn over for a few seconds and then release your foot. This will also cut down on the number of flooding issues.

Detonation DOES NOT HURT a non forced induction engine bad. ALL of the rotaries that are destroyed from detonation have forced induction. The added temperature extremes and greater pressures of forced induction are what really hurt the engine during detonation.

B-Nez

This is exactly why you must be sure and redline your Renesis often - to help keep that trailing hole clean.
Absolutely true. However, I also took into consideration that he's talking about leaning beyond the onset of detonation and going to the point that the motor dies. Surely, that's gotta be pretty bad, too?

Shocka

This is a great thread for people like me who own the car but really do not understand the flooding issue throughly.

since reading this board i usually do not take the 8 for short drives, and if i have to move a short distance; like going to the gas station from my house i will get to the gas station and idle the car for couple of minutes before shut down.

I wish there was a solution for this so that I would worry less when my father takes out the 8 and for those random cases i might just forgot. Someone mentioned a Turbo Timer.. dunno how that would work though.

tpryor

Just a note:

There IS a Mazda mandated fix for the flooding issue!!!

Several weeks ago, my car was having the alignment "tweaked" for the next autocross, and my dealer asked if I had all the updates. I thought I did, but upon further checking, they found I was due the upgraded oil pan AND the "hotter" leading spark plugs FOR THE FLOODING ISSUE!

Mazda has let ALL of their dealer network know, that if a customer complains of "flooding" or "hard to start" issues, to put in these plugs under warranty.

Ask them.....

Shocka

great to know tpryor! thanks for the information. Perhaps a mod should start a RX-8 Update Thread and leave it sticky or something like that.

rotarygod

Yep good to know. I wonder how a hotter leading plug will make a difference since the trailing plugs fire first at startup. Hmm.....?

I definitely agree with the redline every time comment. They are meant to rev.

241Commuter

I don't recall reading that in any of the service bulletins . It would be nice to know, for example, what VIN numbers still require the spark plug upgrades. I'm wondering if my dealer, who is still doesn't comprehend the need for 5w-20 oil, has a clue. It would be disappointing if official Mazda warranty repair updates were communicated to dealers via channels outside the service bulletins.

tpryor

I asked that very question, and they said Mazda did not want to publish a Service Bulletin for this. They were notifying the dealers through the normal communications "channels" (whatever that means), but it WAS an official Mazda communication.

And, it was the bottom two plugs, maybe they are the trailing??

Gyro

This pic will illustrate the above statement by Rotarygod.

This shows the relationship between leading and trailing spark plug exposure. If plugs were fitted in this housing (12A), the leading (bigger hole) spark plug would be visibly exposed. The trailing would not.

rotarygod

Thanks for the pic! Now imagine how you are supposed to fire anything through that, especially when the plug is set back by 3/8". It just makes much more sense to fire the leading plug first, at least on startup. Why they fire the trailing first at all is beyond me. That's why it is called "trailing".

Just for illustrative purposes, the trailing hole is about twice the width of the plug gap! The center ceramic electrode of the plug itself takes up much of that area while the plugs fire to the sides. Some plugs have a small ground strap that comes up over the electrode but even still now the spark has to go around the blockage before it does anything useful. You can not enlarge that hole though due to its location in relation to how far along in the compression cycle the rotor is at when the apex seals cross the hole. You don't want pressure bleeding back around the apex seal into the following chamber. The leading location size does not matter near as much.

Mazda: You guys drink a little too much Sake over there on the job!

rotarygod

Oh yeah, the top plugs are trailing and the bottom ones are leading.

Gyro

Another angle.

Chrisbert

This may seem dumb, but what exactly happens when you press teh accelerator to the floor before starting? Won't that dump more gas into it?

jonalan

Is it me, or is everyone kind of freaking out unneccessarily about this "flooding issue"? According to the polls on this board, over 80% of us have NEVER flooded our engine.

As far as I'm concerned, this isn't an issue. Just follow some very simple rules - don't start your car, let it run for 30 seconds and shut it off (which I would never do anyway, even with a piston engine) - and you'll be fine.

What we're talking about here is the "possibility" of flooding, not an actual flooding issue.

Those of you who have actually flooded your engine, have a flooding issue. And, if it continues, you SHOULD contact Mazda and complain. BUT, those of us who have never flooded our engines, have no grounds for complaint.

I'll get off my soapbox now. As you were.....

MEGAREDS

I don't think I'm overreacting...

Q121825

I don't think folks are overreacting. If it hadn't been for this forum, I wouldn't have guessed (having never previously owned a rotary) such a problem existed. In 3 test drives, not one dealer has ever mentioned it. You'd have to dig AND know something about rotary engines to understand the real importance of the section in the owner's manual about restarting a flooded engine.

Maybe on my next test drive, I'll turn it off right after starting and see how the dealer reacts...

Q121825

That's a sad picture. When will they get it back to you? Nice looking car though. I do like the clear side markers.

And no snow on the ground? In January? That doesn't bode well for the rest of winter.

MEGAREDS

I was pretty cocky before Tuesday. I really thought that knowing what to do when the car flooded was the key. It seems that there is no reliable parachute... just don't do it.

Or, go ahead and give it a shot. Lets all just drive the car five feet and shut it down, then post our experiences... I'll go first... ok, your turn...

They tell me the car probably won't get looked at until Monday. That's about a week without the car. The whole experience just proves that I love my wife more than my car. It's close, but she wins.