Dalcius

Zoom, thanks for the awesome reply.

Offhand how much damage will knocking the rotor do in the Renesis? It's my understanding that it was devastating in the RX-7 (turbo and lower-quality seals). With the new seals and the naturally aspirated nature of the engine, do you think getting this for about a second 5 or 6 times is cause enough to have the engine checked, assuming the problem is low octane gas?

Thanks in advance for all your time

zoom44

oh yeah if you have any reason to believe you are getting knock you should have the dealer service check it out. if it knocked the pcm has a record of it. also if it mis-fired the pcm has a record of it. they may need to just clean or replace your spark plugs. you should also run some high octane gas for awhile and try to burn out any carbon that may have built up. running it up to 9k as much as you can in first and second- once the engine is warm!!- should do the trick. but as i said above get them to pull and inspect the plugs. a good mechanic can tell alot about how an engine is runnign just by getting a good look at the plugs.

knock is bad becuase it can break an apex seal. if that happens then bits of the seal get tossed around in the housing causing big scrathes. then its time for either resurfacing of the housing or replacement with new one(s). on the turbo sevens the bits of the seal would also get tossed into the turbo wrecking the turbo as well.

if you're at all within easy driving distance of Mazda south i would suggest taking it there

Dalcius

That's where I got my car from, thanks. I'm heading there tomorrow. Is there anyone you would recommend asking for in service?

Assuming that what's going on is knocking, would you be concerned about the apex seals after the bit that's been happening with me? I'm not clear on how sensitive the Renesis is to damage.

Thanks again

zoom44

i dont know any of the techs there by name but if you pm hondas2k he should be able to hook you up.

the apex seals are stronger than in any former mazda rotary. it would have to be a pretty continuous knock to break one imo. but as for weaking one over time i am not sure. if theres a problem they'll find it.

DOMINION

I hit warp speed!!!

jwitzer

Update:

M Flash has cured the hesitation problem at 6300 rpm, but the car still doesn't seem to pull well above there anyway.

Oh, well. Wait for the MazdaSpeed edition, I guess.

And 6300 rpm, even in 6th, would be, what? 126 MPH? Where does that count as "warp speed"???

Red-Devil

Hi Dalcius

Here's my story. I had exactly the same problem you describe. My first response, based on some of the posts in these threads was to burn it a bit (up to say 8000rpm in 1st, 2nd and 3rd gears) to clear out the carbon etc. which builds up if you drive slowly all the time, as when breaking the engine in. This seamed to improve the situation, but there was still the hesitation at about 6500rpm.

I took the car in at about 960km (~600mi). They changed the oil and plugs and made sure I had the latest PCM flash (G version in my case). Still the same problem. A compression test revealed that my engine was below the required compression spec, but was explained away by saying that the engine still needs to break in before I can expect to get the high compression values. They still have to prove that to me. They will be testing the compressions on both directors' cars, as well as a new one due in tomorrow, for comparison.

Then they notice while going through all the diagnostics that there was a fault in the electronic throttle body. They brought in the director's RX8 and swopped over the throttle bodies to see if there would be a difference. There definitely was a differece and the hesitation went away. They are replacing my throttle body today with a new one, so I will let you know how that pans out.

I also picked up on another thread that the fuel level in your tank could be affecting things. If you run at too low level of gas, you can get air sucked into the fuel pick-up which could cause a similar problem. If I think back, my problem was worst when low on gas.

Will keep you posted on developments....