I've got a brand new RX8 R3 and for the past couple of weeks i've noticed a weird sputter coming from the exhaust that would cause minor vibrations in the car while idle. the RPMS do not fluctuate. i searched google and found this

https://www.rx8club.com/series-i-trouble-shooting-95/intermittent-miss-idle-normal-194355/

i do not think it would be the coils since it is a new car. any ideas anyone?

 

Mine sputters too at idle. But only the first 30 seconds or so. I think it's because extra fuel is being delivered into the cold engine. I replaced coils plugs wires recently. Does yours do it while warm?

 

yeah it sputters while warm. never had this happen though when i first picked up my car

 

The car may have sat on the dealer lot too long and the spark plugs may have carbon build up from too much idling and not enough driving around. Pretty common for S2's at they don't sell very well.

Check this thread out, also may want to read my post #33

https://www.rx8club.com/series-ii-technical-trouble-shooting-160/misfire-idle-when-fully-warm-2009-s2-10k-miles-209096/

 

Break the motor in and let it rip. Redline, redline, redline. It's not just a figure of speech with the RX's. It's part of maintenance.