About two tanks of gas ago I noticed much more vibration in the gear shift lever, much lower idel (no more than 750-500). Took it in, tech noticed what I did, "cleaned plugs,checked cats) still did it. He called Mazda was told to take it to again "highway speeds" and leave it in 4th. Well it was a tad better but is at it again AND is going back again. Maybe a cracked engine mount? I drove it like a sissy until I found out the tires are shot since then "a little harder". No drop off in power at any RPM although sounds tinner( tin-e-er) if thats even a word? Anyway kinda pissed.

 

I would check the MAF, clean it down with some electronics cleaner, make sure your air filter is also clean, get some redline fuel injector cleaner and run that through the tank. How many miles do you have? You may need new spark plugs as ours need to be replaced every 25K or so.

There was a heat issue with the engine mount near the cat that there is a TSB for, but unless you notice a real bad vibration, its likely something else.

 

mine does the same thing, early production 2004 model. Best bet is to drive a little harder once and a while and clean out the carbon. If you baby the car too much, like shifting at 4k rpm all the time, they will studder a little. Also try running octane boost through a tank.

 

If you have been babying it, as stated above try some Yamaha Ring Free. I use it every 3rd tank or so, for carbon prevention, along with a few redlines per trip. It's about $12 a bottle at my local outboard shop, and you use 2-4 ounces at a time.

 

Is there a 'pop' noise from the engine when you redline it and the carbon clears out?

Sometimes this happens with my car, always wondered about the pop noise, but it only happens every now and again, and I have to be pushing the car hard.

 

i'd say clean your MAF. it's the only thing telling the ECU how hard the engine is breathing.

 

Does your entire car vibrate when your RPM drops? Mine does whenever the A/C clutch kicks on and the RPM dips.

 

Thanks for the input. I just turned 16k and nope the whole car does not shake. The tranny much more so and feel it in the seats. I haven't heard a pop either, Monday I'll make sure to tell the techs about the MAF and maybe an engine mount?

 

Just out of curiosity, what RPM should the engine be idling at typically?

Mine idles at just under a thousand, and sometime dips closer to 750 where is shudders for a bit before picking up again. (Particularly when I have a A/C set at 3 or 4)

Is this normal, or should I have it check out? I have only 1800 miles on my car.

 

This is normal, it is less heard with the stock exhaust, and heard very often with an aftermarket one. All this is, is the unburned gas vapors in the the exhaust getting lit by the heat, commonly referred to as "backfiring" or "afterburning". I hear it all the time in the midrange when shifting in my car.

 

This is normal. Our rotary engine runs very lean at idle and this causes some vibrations and some dips from time to time.

My suggestion is get out on an empty road or a highway and run the car hard in 3rd gear for example from 7k to redline for a couple minutes, and I mean keep it in that ran for a couple minutes, you will notice it idles better and the car just plain wants to run better after doing so.

 

Agreed, I just purchased my 8 like 2 weeks ago (04' w/50k miles). It vibrates a lot when it idles around 650-700. I met up with some other people who own 8's here in town and we went out and drove them fairly rough. The first time I have ever really opened the car up over 7k rpm on and off for an extended amount of time. After the engine was nice and driven it just seemed to run better and sounded better idling. Just my 2 cents.

 

5/1/06 - Revi + Ram Air - 24,000 miles + installed new spark plugs with the Revi. – OEM tires, exhaust, 91 octane.
Idle – the bumble, or rev dip or whatever it is called is gone. Smoother idle now.
Consensus seems to be that the right CAI will improve the idle of the rotary.

 

I just changed my spark plugs. My car idles silky smooth. Before, it had a lumpy idle.

 

just had my 2004 RX8 at the dealership yesterday for dying out at red lights. It has 52,000 miles on it. They changed the spark plugs and did an engine clean, oil change and charged me around $500.00. Driving home today it died at another red light just like before. was able to get it cranked and get home. anyone know what this problem is?

 

There was few post about this "dying at red light when engine turns 50K+ miles"

They replaced some of the engine, correct me if Im wrong (You need to be agressive to be able to get them replace it after warranty for free)

 

i just heard today that several RX8s had to have engines replaced, the early 2004 models

they still say they dont know what is wrong with mine after being in the shop a full day
getting worried now

 

wow,
never heard of that. you should post this on the disscussion section...

beers

 

im down here in houstin, tx n its raining really bad, i have the AEM installed n the greddy sp2, i was waiting at the light n the rpm's just dropped a lil n then bounced right bak up, a gave it a lil gas but it didnt die on me so i was ok, the drive home was alright, no problems or nethin, wen i parked in my garage the rpms died down n bounced bak up again, but it didnt die on me, im just curious if this ROUGH IDLE has nethin to do wit the rain n my AEM?