Rough idle, anybody else?
 

Hi guys....

I've noticed excess vibration while I'm idling in traffic.. being that I'm almost ALWAYS driving city (and thus, my best gas mileage has been 17mpg), it's really irritating.

Anybody else have this problem? Should I take it in?

the car i test drove shook a bit at idle too... especially the shifter

yeah, my shifter has the shakse at idle also
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Weed Vaporizer

My shifter shakes a little but not enough for me to worry about. What is your definition of "rough idle" and how bad does your shifter shake?

Ahhh, the dreaded rough rotary idle. By lightening up the rotors in the Renesis, I am suprised this hasn't been more of a problem. Considering how important the balance of the rotors are, and the Renesis using light rotors, would even the slightest carbon buildup cause a vibration at idle? I keep hearing about the rich a/f setting at high rpm, which will leave alot more unburnt fuel in the engine, especially with exhuast side porting instead of periphial porting. Wasn't that the point of the side exhaust port- to aloow the unburtn fuel to stay in the engine? This could also lead to fouled plugs-- either way, maybe it is time to start mixing some MMO in the fuel for your Renesis?:p

So what should I do? Should I take it in, or is it something thats normal?

I guess you could take it in and have them put it on a scope, but it it really was misfiring (and I can't think what else would be causing a vibration at idle) I would expect it to throw a code.

my car only has 130 miles but i have noticed something odd,the car i test drove first before mine arrived had the shifter shake at idle but did not idle rough.my car i bought yesterday does not idle rough either and still has the shifter shake but is only half of what the first car i drove was(if that makes any sense)by the way,i love this car.

Could the shakes be caused by spark plug/coil going out?
My car shakes at idle slightly and almost skips a beat every 10-20 secs, yet no code other than the evap code i havent addressed yet.

The shifter shakes because it is a top loader transmission and that is the vibration you feel in the transmisison. My dad drives the Miata MX-5 and the shifter does the exact same thing so I would not worry about it.

Hi everyone,

my rx9 Idle stall in the morning after 20 of driving stops.. I have change the ignition coils, MAF sensor, new spark plugs.. does anyone has and idea of what this could be?

please help.. thank!

rx8

Weelllll. A shaking shifter is normal. As long as it is idling at 900-1k and not dropping that's normal too. If it is shaking more than you like, get the carbon cleaned. If that doesn't help, check the engine mounts. Otherwise get used to it. C:

You do know the original post you quoted is almost 9 years old? ;)

Then I guess we should be responding to this guy, since he's the one that bumped it up. :O

yes is a rx8

yes, and my rough idle was fixed with new spark plugs. had 36K miles on original. prior to this, like op stated, i had rough idle with slight vibration every 15 sec. and when it does the rpm drops about 200 and back up.

Wow thats excactly my problem where it shakes some,but more importantly drops 200 rpm every 5 seconds or so.
Motor mounts are very common to go bad and for people with shakes but no idle drop that seems to be the culprit. I thought if the plugs are bad it would pop a misfire code?? hmm can you buy plugs without the coils or are they a package deal?

Cheapest you will find anywhere.