NoName

OK, so I am a virgin rotory owner here, Just got a New RX8. ! have just short of 1000 miles on it. Why does my car fall on its face at 6500 rpm,s. then pick itself up. I drove a different one and same thing. why?

nzarnow

For this car, that is for sure the sweet spot of the car. If anything, that should be about if not a little higher of where it is the fastest.

Kinda falls on its face before 4k RPM then takes off.

Ike

The 3rd port opens right before 6500 RPMs, that's most likely what you're feeling.

NoName

if it is the 3rd port opening then why such a "wait" and what do you mean 3rd port. I fell like I know nothing here. I know a V8 pretty well, not a rotory

Renesis_8

Its Mazda's secondary V-TEC opening

Renesis has 6 Intake ports

First two are always open

@3750rpm

Third and Fourth opens

@6250rpm

Fifth and Sixth opens


--- A little searching : https://www.rx8club.com/showthread.p...e+port+opening

You can probably learn all of it in that thread
________
Web shows

NoName

Ok, Thanks. Now I understand.

KYLiquid

I had a bit of a stumble as the ports would open at 6250, my guess was that the car wasnt getting the fuel mix right for a split second when all the extra air came in from those ports opening. So I reset the ECU (there is a DIY on how to do this in the DIY section) and that seemed to help quite a bit, now its smooth from idle to 9600!

NoName

I could not find anything in DIY. can you tell me something about this

KYLiquid

Hrmmm, I know I saw it somewhere....

I did a search and couldnt quickly find it, so I will just post instructions for you :

There are 2 kinds of memory in the RX8, so there is 2 differnt methods to clear both of them (one for each).

1) Get in the car, turn the ignition key to the 'ACC' position, I think its the first click. Then tap the brake pedal 20 times in 10 secs, basicaly tap it as fast as you can, you should see the Oil Pressure Needle 'sweep' from left to right and back...if you do, your done, if not, try it again.

2) With the car off and the key out press and hold down the 'trip counter reset' its the black peg just above and to the left of the tach. While holding it down, put the key in and turn to the 'on' position, I think its 2 clicks, but dont start. Keep holding the 'trip counter reset' down, youll notice where the ODO/Trip meter is a bunch of stuff will pop up on it. You can release the 'trip counter reset' now, if you want you can push the 'trip counter reset' several times to cycle thru a bunch of functions, dont worry your not chaning anything, just viewing it, it will test various lights and displays in the gauge cluster, eventualy you will get to a point where pushing the button doesnt take you any further, I think number 50 or 55 or soemthing, anyway, just turn the key to off, remove it, and then you can start the car, and drive like normal....the car will start to relearn your driving again. You can also skip that last step and just turn the car off and start it withough going thru all those menus.

Hope that helps!

Note: Resetting the ECU man cause that tank of gas to have differnt economy, as its resetting all the fuel and timing maps to factory, so it will use more/less fuel than normal. Its not a big deal, the car will learn your driving habbits again in about 1 tank of gas or a few hundred miles....if not sooner.

Keep in mind the car adjusts it-self to your driving style....so its good to belt out some higher speeds (80's) and upper RPM, redline or rev limiter, at least once a week...esp if all you do is city or stop and go driving. It will help keep the motor clean and happy, as well as keep the ecu adjusting.

I reset the ECU in my car about 4 times a year, or after any power mod. The reason, well I change it with the seasons, as the temp and humidity changes thru the year, the car will slowly relearn and adapt to the weather, but id rather just force it to change quickly to get the best performance for the conditions...ect. Reseting it for mods is just so the car will retune its fuel/timing maps for the new parts...IE intake, exhaust, ect....although it doesnt make a huge difference.

Good luck, PM me with questions.