I wonder if your infrequent redlines contributed to the intake manifold replacement. Did they say you had to have the manifold replaced?

 

You've stumbled on to the very best way to build up carbon and have to replace an intake manifold all in one. The tertiary and VDI intake events happen at 6250 and 7500. If you are not exercising them regularly they can become stuck in place from carbon build up in short order. A 6 mile drive to work is great for keeping the commute time and gas bill down, but it's barely enough time for the car to warm all the way up.

the shift buzzer is your friend

 

...and my next question is... although I redline at least once daily I have been wondering how a gentle half throttle acceleration through 1st, 2nd and 3rd up to redline is to keep the carbon out and intake valves operating vs a more aggressive almost WOT exercise. Also, does would it be beneficial to run at 8000-8500 for 10 seconds or so in 2nd or 3rd?

 

Don't get too hung up on this; imprecise science at best. Hit the redline when you feel the need (which for me averages once daily and dump some STP or similar fuel system cleaner in your tank every 4,000 miles or so and you'll be fine.

 

I understand. I do, btw, premix with Idemitsu.
I'm wondering whether your 'imprecise science' is based on theory, surveys from other forum members, "new engine club" member experiences, teardowns of RX8 or RX7 motors or just good ol'gut feel?

I've often wondered how many engines have been replaced or required major work if they hadbeen premixed, driven to redline once a day and maybe run oil heavier than 5w20. That would be an interesting poll. My guess is,with that combination of treatment, the number of MT '05 and up engine problems would be VERY low.
Based on my reading here on the forum, that combination should produce some very good reliability figures.

Speaking of reliability, the Star Mazda Series / Formula Mazda cars use our
13B engine and they claim that the reliability record is excellent, and unlike other formula x series cars and engines, the Renesis engines last an entire season and do not require teardown and rebuild mid season or post race. I watched one of their races a few weeks ago and it was amazing to watch the entire field running WOT for most of the race ... and I don't think I saw any mechanical issues.. engine wise. Pretty cool ... and a tribute to the RX8!

 

Well thats it, I will make it my duty to hear the buzzer at least once a week.

What I am interested in the most is seeing if it has fixed the one problem that has occurred since early on. While on the highway cruising along at 80mph, sometimes going up a small hill/incline, the car will lose 10 - 15 mph. Even pushing the accelerator all the way to the floor, doesnt help. Then in ten to twenty seconds you can feel the power all of sudden kick back in. Its been to Mazda many times about this, but of course never happens when they test drive it.

 

Several people had this problem before the '06 recall. Mazda got the bright idea to reduce the oil coming from the OMP on long cruise situations. No oil on the center of the apex seal = reduced compression and increased wear. The '06 recall flash should have taken care of it for you, but your OMP may still not be puting out enough oil at a steady cruise. You should consider premixing 3oz to 4oz per fill up (about 13 gallons when the fuel light comes on).

 

Once a day is good for the soul (and the engine too I believe).

Did you have the new decarboning TSB done? This is separate from the new flash and it's intended for cars that have experienced loss of power.

 

Yeah car went in with CEL on and they did the decarbon procedure and the flash, six hours later CEL was back on. Next step was them replacing intake.

Just got back home and twice took it above 9k and no damn buzzer, WTF?

 

Mileage improved for new TSB drivers?

 

Coupla things. The rotary loves to be revved up. 2ndly, these cars despite seeing harder use also gets proper attention from knowledgeable mechanics vs. joe public.

 

I seem to be getting about 10-15 extra miles per tank. I usually fill up when the needle's around 1/4 tank. I was usually at 210 miles at that point, filling up with 11-12 gallons. Now I fill up with the same amount of gas but I'm at 220-225 miles. I've filled up about 10 times since the flash.

 

To get that kind of empirical data one would have to measure many variables over time, which I'm confident Mazda quality assurance does, and will hopefully lead to ever better rotary designs (larger thermal mass and direct fuel injection for the 16X for instance). My 'imprecise science' is a combination of common sense, experience as a multi-discipline engineer and age.

I run 5w-20 year round (cooler climate my area; infrequent Winter use) and pre-mix 4 oz/tank Idemitsu in the Summer, along with the fuel system cleaner mentioned. I typically use a quality detergent gasoline as well (Mobil or Shell).

 

Got the MSP-16 flash done

Feels more responsive between 3k to 5k, feels like before from 5k to 7k, then after 7k to redline feels stronger then before

car still idles the same, i think im getting slightly better gas millage.

overall, yes i can feel a difference by the seat of my pants!!

 

No, I think he's saying that it's not working now.

 

Yeah I have heard it before, but have to admit it has been awhile. (Bose can drowned that out easily). And I have had the car since new. It just didnt come on the other day. And the weird thing is I went to about 9300 rpm before letting off. Isnt the car supposed to prevent the engine from spinning faster than 9k?

 

Nah, the cutoff is usually around 9,200, but I did once cause it to rev to just under 10,000 by clutching at the right moment when accelerating downhill.

 

Took my 04 6spd in on this, also had them check the milky dip stick and some idle vibration. They ended up replacing the intake, replacing an engine mount, and doing the pcm flash.....my 8 is running soooo much better. Was not running 'bad' before, but it's much smoother acceleration. Thanks for posting information like this. Also good reason to keep coming back to the boards even when you are 'content'.

 

a lot of us see 9500 on the tach before the limiter hits, but the reality is it's only 9000 rpm in actuality, the tach is off that much on the upper end

 

Had the PCM flash done last friday. Seems to run about the same but perhaps a bit more stable at low RPM's. I'm happy with it. Now if only I could get the dealer to replace my gas tank filler neck...

 

Had my msp16 done yesterday. Hard to tell the difference but idle does seem smoother and perhaps a bit more power.

 

For me the idle was smoother right away but I did notice a bit more power after day or two.

 

Looks like this might have become an official recall. Logged into my owners page on mazdausa.com this started showing up:

----------------------------------------
Recall Warning

Date: 03/14/2008

RX-8 - Engine Lack Of Power
RX-8 Voluntary Emission Recall
-----------------------------------------

I'm pretty sure that the lack of power wasn't there last week even though it says 3/14. I've got an 04 with an early vin so it may not be all 8's.

 

Had the MSP16 performed today. No difference. Before, the engine always fired right up, idled smoothly, and had gobs of power. Still does.

 

I'm seeing this too on mine. I will try to get this done this week and report back.