Questionable Idling...............thoughts??
 

The car stalled on me at a red light New Year's Eve day, about a week later it almost stalled. Right now it has ~3200 miles on it. Half that amount a ago is when I noticed the idle wasn't always consistant.

You know when you drive a vehicle enough, that you get to know it so well, that you can sense things with it that any other person may not notice?

Even tho PCM had a reflash at my first oil change, something the service center said my car needed, it still seems to idle rough. I mentioned the idle thing but they said they couldn't tell anything.....? Here's what I notice and tell me if you notice the same thing with yours.

{after it's warmed up}
The car will be idling, doesn't matter where or how long it has been running, it feels as though the engine chokes a bit. By feel I mean, that I can feel it through the seat. Mind you, it's not that the whole car is vibrating because it doesn't, but it's slight. Most of the time, the roughness is not enough to register on the tach because it is so slight. Every once in a while, i'll see the tach drop just below 750. But IT IS there!

Now this idling, is with nothing else on; no radio, no a/c, no heat, no lights, nothing else is engaged that I would consider bogging the engine down. Other than that the car runs great, no issues mechanically anywhere else.

Is there anyone else experiencing this, or even something remotely like this?

I plan on getting it to another service dept at some point, the only problem is, how do I convince them that I really do sense something isn't right? I KNOW they'll look at it and say everything is just fine; as I have heard from many techs over the years with many vehicles.

As slight as it is, I can feel it, I can hear it. My RX-8th sense says so.

Thoughts?

i cannot say i've experienced a rough idle to the extent you have. it has not stalled since i bought it. the shifter vibrates at idle but not much. there is no hesitation whatsoever when accelerating. i do 90% city driving so i'm sure thats not too good for it although i try to rev as high as possible at least once a day. good luck.

I have this problem and it sounds like its worse for me than you. Sometimes its only subtle but other times its really rough and I reallyfeel it on the steering wheel. But I see nothing on the tachometer when it happens. I thought something was going on w/the transmission but I dont think abad transmission would cause the entirecar to shake like it does for me for so long. An example ofthe problem is I would stop at a stoplight and have my foot on the brakes andthere would be a somewhat noisy vibration that both driver and passenger could feel righton their seat and it wouldnt stop vibrating until the light turned green and I took my foot off the brakes. I am disappointed aboutthis b/c the car doesnt even have 5000 miles on it yet. My Rx8 is auto btw but it sounds similar to your problem I think.

I had a rough idle problem.....................

I revved the S*** out of it and the problem went away. I think they must need it to move any deposits that are builing up on the engine.

Did you modify your Intake at all?

If you did, or the filter isnt installed it can cause the car to idle rough and stall.

You might want to check your airbox..

Just a suggestion.

Also, maybe it's something wrong with the Mass airflow sensor?

Every now and then I will notice the idle drops when I am sitting at an intersection, but it is very brief and never has stalled. I have almost 6k on the car.

I use to own two RX-7's. Every time that I would have a tune up done, the Mazda tech's would always seem to set the idle too low. In warm weather it did not matter, but it would during cold months after start up. What ooski explained sounded just like what would happen to me. I would always take the car back and ask the tech to up the idle. You might try that.

OOSIk, why did they tell you that your PCM needed to be reflashed?

They just said my car was due for a reflash having to do with mileage and power, nothing specific, the paprework shows they did just that. figured it would take care of the idle thing...apparantly not.

No mods have been done to my car, all still stock.

The idle isn't adjustable on the RX-8.
Neither is the timing or anything else that was once sevicable on other vehicles.

The issue may be fouled trailing plugs or a vacuum leak.

I had the same problem when it got cold here (below freezing). Dealer told me to not run premium gas and switch to unleaded. I thought he was full of it but I asked the Mazda rep when she came by and she confirmed the same thing. Said they have had a problem with it here in North Texas. Switched to regular gas and have been OK since and it was below freezing this week.
Also see the thread I posted
Just an idea.https://www.rx8club.com/showthread.p...threadid=18646