Obsolete

I'm new here so I'm sorry if this has already been answered. I tried looking around for something close to the problem I've been having but I didn't find anything. Anyway, for the last week or so (after I got it back from the Mazda dealership for an oil change, tire rotation, and full service inspection) I noticed it's kind of like sputtering after I start it. It starts up and drives fine but it's like there's something wrong with the exhaust that makes it sound like it's "spitting" or something. It's done this before I think? But it was never this bad and it eventually stopped doing it. I've never had any issues with my car until now. I don't know a whole lot about servicing cars so bear with me. Does this mean it could be carbon buildup from NOT red-lining it at least once a month like I should be doing? Or clogged CAT or fuel injectors?

Also, another problem I've been having for a while now (even before it went in for service) I've noticed is the acceleration is sometimes "unresponsive". Like when I'm behind someone and I go to pass them it hesitates and takes a second to "kick in". This usually happens between 1st and 3rd gear.

Does anyone know what could be causing either of these problems or what it might be? I've had my RX8 for 2.5 years now and I've put 15k of the 45k on it. It's a 2005 RX8 AT Shinka. As per some of the other threads, I haven't had a compression test done yet. I also haven't had any plugs or coils changed. I figured I'd register here and ask you guys since you seem to know what you're talking about from reading threads and doing research on it. Any help would be much appreciated!

kingdan2

I dont know about the sputtering but I was wondering what rpm your car is at when it hesitates to accelerate? are you downshifting before pulling out to pass or just flooring it? The rx8 does not have a lot of low end torque so its important to use the upper rpms when you want to accelerate.

Obsolete

Thanks for the reply. It's usually between 2 and 4k RPM's when it hesitates to accelerate. I just ease the gas. I never floor it. This usually happens when I'm driving in 'automatic mode'. I drive in this mode when I'm computing to and from work because there's a lot of stop and go traffic. Is there anyone else that might know what could be causing either of these problems? Any other advice would be great.

ShinkaEvo

iTrader: (3)

2-4k rmp is consider low rmp for rotary, it'll normal for it to take few sec to kick in.
You might wanna redline it, in manual mode, once a day.
I usually keep it around 5k rmp if I want better response in acceleration.
And you might wanna change your plugs and coils....

The sputtering is normal, unless you got unusual smoke coming out or CEL...

If you want faster response, drive in manual mode, keep the rpm up there.