I would love to see some statistics. However, it would be safe to say if you have an early build and the engine has not gone yet you are pretty safe.

 

I am at 70,000 and will be doing the plugs this weekend.

 

Mine started cutting out at full power.

06 with 24K needed plugs, no coils. The dealer also ran the clean out for carbon, twice because it still cut out. Now it runs like a top.

I was idling mine way too much and now avoid that and run it to higher rpms.

 

I dunno, my '04 made it to around 78,000 miles so I figured I was safe too. It was just taking a little longer to start now and then when hot, and didn't quite accelerate as hard as it should on occasion. But it wasn't anything dramatic, nothing a stranger driving the car would have thought OMG! about.

So I actually took it to the dealer thinking it was just plugs and coils, but had them do the test just in case, and... it failed

And now with the new engine, the differences are very obvious. It's just when the engine slowly weakens over 30,000 miles or so, you don't always realize it happening. They don't normally just blow up one day, it just gets weaker and takes longer and longer to start when hot.

But like 9krpmrx8 said, I've gone through loving it, then resenting all the hassle this last year with getting a new engine (though I am VERY grateful to Mazda for this) and spending thousands in pre-emptive maintenance, but now that it's perfect again... I love it.

It really is an addiction. It's crazy, but I kinda agree with someone's half-joking about the engine being considered a "wearable part." The car is just that unique and enjoyable.

 

^ Yep. A typical driver would have never known my first two engines were low on power. It wasn't until they eventually started stalling that drivability was affected. SWG (local SARX member) had the engine in her 2007 GT replaced recently and hers died the same way, slowly over time until hard starts and eventual stalling started happening. She is the first 07' of our group to go. So far we have had a failure in every year except 2008 (no current member with n 08") but one of the SARX guys is a tech at Mazda and he said they did a replacement in a 2008 40th model. And of course none of our Series II members have had engine issues.

The idea that is was due to the OMP flash and oil choice is just BS because plenty of us had failures running factory recommended dino oil and had the latest flash. My second motor ran Castrol GTX and had the latest flash from day one. Granted that engine lasted the longest (74,000 miles) but that was more due to the fact that I was OCD about caring for it.

Either way IMO, I don't think you can realistically expect a Renesis to last much longer than 75,000-100,000 miles. But if you live in a cool environment and are very maintenance conscious then it is definitely possible.

 

That makes me worry. My car has been acting like that, with the hot starts and everything. I figured it was just time for plugs. I guess I will see this weekend. If not I'm going to the dealer next week and do a compression test.

 

Well don't jump the gun, hard starts can be due to a couple of things.

 

Well according to the history of the car the plugs have never been changed. The coils and wires were done about 10k ago. I'm picking up new plugs today and they will be in by this weekend. The starter is original as well.

 

NNNNNNNNNNNNNOOOOOOOOOOOOOOOOOOOooooooooooooooooo. ...............

My 40th has just under 25K miles and running strong as far as I know. I redline in 2nd (65 mph) often. Castrol GTX 5w30 it's whole life and Lucas oil UCL every fillup. I don't run 2 stroke because where I live in VA we have to keep our CATs.

I'm thinking of switching to Syntec 0w30 (german castrol) next change.

 

What extra maintenance stuff did you do to qualify for OCD? I'm changing oil at 3K or less, changing coolant and plugs sooner than recommended, will replace current coils when they've got 30K on them, etc.

I'm not goofing around or anything. I love this car and want to make it last as long as possible. Need to be obsessive!

Ken

 

You should be good to go, you are not really operating in a harsh environment. I mainly commented because some think the failures are more common on 04'-05' models and that is the case but only because of the age and typical mileage. There were no significant mechanical changes from 03-08 6 port manuals that would prevent the later models from failing. That is why the dealers are now seeing the 06's and 07's coming in for replacements because the mileage is typically getting above the 45,000-50,000 mark.

I ran GC (Castrol Syntec 0W-30) for a while and had it tested and it wasn't bad but it did not test as good as the Mobil1 and Rotella T6. But, if you are not running the SOHN adapter I suggest just sticking with the Castrol GTX and changing it regularly, it tests and performs very well. Look for my thread on used oil analysis'.


Well I change the oil at usually under 3,000, I premix and run the SOHN, I try and use the same new gas station near my house because of the new tanks and filtration method, I never leave my driveway without the oil temps being up to normal, I change coolant once a year despite mileage, and I only run a quality WIX air filter and change it once a year despite mileage.

The air filter thing is going to be tough with the turbo because I actually find myself thinking about how much dirt and grime will get past an aftermarket reusable filter

My last motor failed due to a fluke and it was especially frustrating since I did everything I could think (all of the above plus no cat, BHR kit, etc.) of to extend it's life. But Pineapple racing should be reporting back soon with a tear down report of that old motor and we will see if premixing, sohn, oil choice, etc. did anything to keep the internals pristine.

 

My 40th just hit the 15K mark. I usually redline in 3rd gear. I've been premixing though, with Pettit Racing Protek-R. I've been told synthetic premix does not damage the cat. I hope I'll be ok

One of the scariest things about buying the car has been the so many horror stories about blown engines - especially stories like yours where owners did EVERYTHING in regards to maintenance and the engine still blew. It really made the decision of buying much more difficult.

In order to deal with that anxiety, I've just convinced myself that my engine will blow too one day not matter what - although I realize that there are better chances for a longer engine life with good maintenance habits.

Also, since mine is an 08', I know I still have 4 more years of engine core warranty. So I know I'll be covered until 2016 - which is good. Also, my has the mazda pre-owned certification which covers a couple of other things as well.

But that "fear" of the engine dying is almost always in my mind. The only time it disappears is when I get in the car and start driving. I enjoy driving this car so much, it's unbelievable. I've never enjoyed driving a motor vehicle so much before in my life before. Another thing that takes engine-failure fears out of my mind is the design of the car itself. It is a head turner, and quite frankly - to me - the RX-8 is one of the most beautiful cars out there.

But I would say that, if the RX-8 didn't handle as well as it does, I would have never bought one

 

Well for me it was a hassle but I had the factory warranty and then an extended 100k warranty on top of that so I never paid for anything aside from mods up until this motor replacement. But if you plan on buying an RX-8 and keeping it for many years then buying a used one with decent mileage is not smart if you are looking for reliable transportation and are not financially sound.

And honestly, this engine rebuild/turbo build process has been really fun. I cannot wait to beat up on some "faster" cars.

 

Always good advice when it comes to sports cars.

I'm kind of entertained by the risk aversion that runs through these threads. I remember the days when if someone wanted a Jaguar they just got it, and accepted the fact that it was certainly going to leak and might have something expensive break. At least the 8's not going to leak.

I want to keep mine for a long time because I don't have a clue what I'd buy if I had to replace it. Different from the Accord that I kept for 23 years because it kept running.

Ken

 

I agree, I have owned many trouble free Hondas, Subarus, and Nissans and they just got boring with time (except my 82' 280ZX Turbo). This RX-8 just keeps me interested and honestly there is nothing out there that excites me (in my price range anyway). Besides, I have been a car guy my entire life and if I didn't have something to wrench on I would go bonkers.

 

What warranty was that? Did you purchase additional warranty from Mazda?

I have another vehicle so I didn't buy the RX-8 for "reliable" transportation. I don't really depend on it to go to work. I realize a sports car - any sports car - is not your typical Honda Civic commuter that runs for 300,000 miles without an oil change, lol. I bought the 40th AE used with low miles mostly because it was the model I really liked the most, because it had the extended pre-owned certification warranty and because the price was right for me at that time.

Also, after researching as much as I did before buying, I decided not to buy one with a ton of miles knowing the life expectancy of these engines is so short anyway. In other words, I wanted to be able to enjoy the car for a few good years before having to deal with engine replacement issues. Lots of great deals out there with used cars with over 50,000-75,000 miles. But I didn't want them as with many of them the engine warranty expires next year.

Anyway, I did freak out when I started having issues with misfires with my 8 a month after I bought the car, and when I thought the dealer lied to me about the compression test results. But I think that's reasonable. Meaning, I don't expect the car to be perfect, but damn, I wasn't expecting to run into those kind of issues just weeks into owning a car with such low miles

I'm past that now

Ha, ha, that makes sense, lol. Really, wrenching is what makes these hobbies interesting. I'm not wrenching on my 8 yet, but I have on my truck for many years. Wrenching is the best way to get to know your car.

I read your earlier post about your local dealer going on 400 plus engine replacements. That's a pretty disturbing figure for a single dealer. I would be interested to know what is the national % of engine failures by region. Does it happen more in hot climates? Did people that gave proof of consistent maintenance had the same failure rates as people that did not care about their cars?

And finally...are the Series II the holy grail or RENESIS reliability with all the mechanical upgrades they have? Probably too soon to know - especially since we don't see so many of them out there -, but I almost bought an 09' and I wonder if I should have

 

I called my local dealer to get some background on my new '05. He knew me previously as I purchased a bunch of stuff for my MSM. I casually asked, "So, have you guys done many engine replacements?" His answer, "Tons." Hehe. Basically told me best of luck, you will have to replace it one day, and that he would not recommend the car to anyone. Said Mazda has a great lineup, but the RX-8 isn't part of it.

Ho hum. Strangely, I was so paranoid about buying one of these cars for that reason, but by being on here, and reading about failures time after time, it doesn't scare me anymore, hehe. You kinda just rebuild it and move on.

Something to be said about a car whose main component craps out and people just keep replacing it and driving it. Any other car and they'd be filling up the junkyard.

 

I have the same problem with my shoes. The soles - arguably the main component - keep wearing out. Yet I just get them replaced and move on.

Ken

 

No I had an extended warranty thru my credit union. The company was named federal or something like that. It was actually pretty good, I had a $100.00 deductible but it covered coils a couple of times, ABS modulator (big bucks), alternator (expensive), starter, and few other things. plus, basically all the extra **** the dealer tries to charge you for when you are getting an engine replacement at the dealer.

I am pretty friendly with my service adviser after 7 years and one of our local RX-8 owners is a tech at that dealer so I get some good info. Now granted this is the biggest private Mazda dealer in Texas but that is still a high number and when my buddy worked at another local dealer here in SA he estimated he alone had done 50 or replacements in the few year he worked there and that is a small time dealer. So when you consider there are 5 Mazda dealerships her in San Antonio alone you can get an idea that the failure rate is pretty significant. As for SARX, there is only a couple of guy that have not had replacements and there are 7 of us who have had more than one replacements But we also have 5 members who have had multiple RX-8's and we have two husband and wife teams rocking his and her RX-8's which is somewhat rare but really cool.

I just love the car so much I can deal with some down time and expenses. It makes you appreciate it so much more when you get it back. I think that is why so many people come back to it. We have had three R3 owners locally who all owned Series I RX-8's prior to buying the R3's.

Maybe San Antonio is just an RX-8 lovers city

 

That extended warranty you had was pretty good!!!

Also...wow...that is one significant number of engine failure/replacements in that area.

 

I'm still on the original engine only because I'm waiting for my dealership to replace my engine.
I made it to 82,3xx and it's still running, just not giving the same power like it used too.

IMO, I would still be on the original engine if one of the Mazda tech's didn't over-fill my oil to the extent of causing misfire on R2 (causing CEL) causing the cat to be clogged and basically not being able to diagnose a problem with some sort of vacuum leak which caused extra stress on the motor.

 

I just wanted to point out that if you go to any car forum there is going to be problems with the car that it is dedicated to.

My late 80s Ford Taurus had a million posts on its forum about how the transmissions were going out, or how the fan for the heater would constantly fail.

People on the 3000GT forums have constant problems with the shaft that runs between the transmission and engine failing. And on the AWD models the transfer case failing.

I haven't had any problems with my RX8 so far (knock on wood etc etc) but then again I am only at 39k miles or so. Whatever car you buy you are probably going to have some sort of issue with it, just get what car you want.

 

That's true: car forums are basically places where people come to find solutions to their problems - or to complain.

However, one thing is to have some things go wrong with a car and the other is to have a high volume of engine failures.