I have the same sounds in my engine...my mechanic said to put a higher grade of gas in the car (although I wasn’t able to reproduce the sound...)...I'm going to try that...see what happens and report back...he also suggested fuel injector cleaner that you put in the gas tank..

"When the rotary engine starts it inject oil directly into the engine...and this will clean the residue out.."

I’m going to try both of these suggestions...if you find anything before me...let me know as well..

Keith

 

I think I know what you guys are talking about and have the same issue.

WIth my case, I get the rattle under hard acceleration starting around 3k RPM and it lasts until about 4000-4500. I thought it was my engine too, but recently had it replaced and still have the same rattle.

I've narrowed it down to 3 things that I'm going to investigate a little further:

1. Engine mounts (would also explain the minor shaking I have at idle)
2. Heat shield
3. Loose exhaust hanger

The sound seems like it's coming from directly under the center console or a little bit infront of it, but I can't reproduce it outside of the car. It's not gas as I always use 91 octane.

I don't have any powerloss (at least not since the new engine). Those of you should see about getting your engines replaced.

 

I have the same as you explained...so you think it is one of those things??? Interesting.

 

you dont think that it might be a bad CAT. converter?

 

Had my cat replaced as part of the recall as well and still have the rattle...

 

ok...
was the engine part of the recall? i have yet to go and take advantage of the recall.

Could this be the tran. slipping thats what it feels like.

Keith

 

I just had my engine and motor mounts replaced at the same time when mazda did the recall work and my car still has shaking at idle. I'm due for new recall work so I'll see what happens. I think its time for engine #2.

 

there has to be something that we are missing...do you think that you need another engine? WOW.

 

You guys won't believe this, but I just recieved my car back after 1 MONTH of being at the dealership for the recall. I got a new motor (which of course includes new plugs), starter, battery, and 1 engine mount. Guess what, it still idles like ****. In addition to that, when I feather the clutch gently to get a slow start, something else unknown rattles violently. Fortunately the new engine seems to be running strong. I'm still breaking it in and thus keeping the revs under 4k, so I can't really say for sure. There's also a new 'farting' sound coming from the exhaust that's especially noticeable when I let off the gas while still in gear (engine breaking). It's interesting that a new motor sounds so different.

Car had 30k miles and is a 2004 6-speed with GT package.

 

I am having idle problems too before and after they performed recall... no new engine here though. just new coils, reflash, CAT, and plugs.


That rattle noise I heard also before the recall was done... Now it is gone... Apparently that is the engine misfiring. Since there was evidence of mine misfiring... and it had this noise for quite some time.

WIth the new Ignition coils... I haven't heard that noise at all at any rpm and the car runs smooth while driving... But the idle issue is still a problem.


It must be something not directly related with the "physical" engine..

 

If the idle problems are due to our cars misfiring, Do you know how many threads and people on here have responded to threads of this manner with the same idle problems? and me, I just got a new engine and still have rough idle. God help us all lol

 

Yeah no kidding.. Bringing my car back on Monday to get looked at.

Will see what will happen.

 

I know no one has posted on this thread in a while but I have the same problem as described in this thread. I have a rattling noise that occurs just as I begin accelerating. I have a 2004 6 speed with about 58K on it. I don't have any problems in idle, however I do have terrible gas mileage (around 180 miles a tank city, maybe 280 highway if i'm lucky). I had an idea that it may be my transmission, but based on what I've read it sounds like it may be my engine. Does anyone know if this is definitely a sign of needing an engine replacement.

 

im having this same issue...kinda. i noticed it one day when i was driving back home on the highway ( about 175 miles ) and it would happen around 3,000 rpm from 1st to 4th gear ( if it happened in the other gears i couldn't hear it). i thought it was just because i had been driving for a couple of hours but it has started back up here recently. it usually only happens from 1st to 4th ( 4th gear being the loudness or most audioable) at around 3,000 rpm. its not a very loud rattle though. you have to really listen for it and it sounds more like metal on metal.

i have also noticed here lately that my 3rd gear kinda grinds when going from 2nd to 3rd at around 4,000 to 4,500 rpm.

any suggestions?

 

I'm having a similar issue on my Series 2 engine with ~10k miles. I noticed it a few weeks ago. Only happens when in-gear, any gear, accelerating (both hard acceleration and normal), between ~2500-4000 rpm. Its a pretty faint rattle and can easily be covered up by road noise or traffic around me. But I deffinitely can hear it clearly on a smooth road with no other traffic around. Took it to the dealership and had the service manager do a ride along with me, of course he couldn't hear anything.

I think it could be somehow linked to the transmission. I've noticed the transmission has been a lot more notchy in the cold weather and it sometimes almost feels like the clutch isn't disengaging all the way. A few times it has even felt like I was popping it out of gear when shifting to neutral. The transmission issues go away when the weather warms up, but the rattle noise is still there. Maybe they aren't linked.

 

What gas do you use reg-87oct or prem-91?

 

i only use prem 91

 

Please give us some more info...model,year,miles,etc... What service and parts has the car had?. How many miles on plugs,coils,wires? What other mods have you got?...How long have you had it?... Have you ever done a de-carbon cleaner?

 

2006 rx8 i think it is the sport but im not for sure 22,000 miles. i haven't added any mods to the car...yet but all i have really done to it so far is the air duct fin removal and changed the oil every 3,000 miles. i was reading in another post that the heat shield around the exhaust can sometimes cause the rattling im hearing. it sounds like it is coming from underneath the center console. around the area were the cig lighter is. i have not done a de-carbon clean but i do red line it once a day . i have had the car since may of this year. would carbon actually do that though?

 

If it's a "rattle" yes it could very well be the shield. If it's a "hammering" it could be preignition and our engine do build up carbon from around town driving, flooding, short trips , carbon will be a hot spot and preignight and cause a "MIAC" (Marble In A Can) sound. Not a good thing for the engine.

 

ok guys you might not like me but i have an 04 127, miles and mine did the rattle and when you are in 2 3 4 you try to speed up it rattles right ? ok if thats the case you need to go get BG syncroshift or on that lines and put that in yorur trans and thats should stop it how i know is that i put redline mt-90 same rattle RP same Kaaz same BG no rattle so try that it worked for me

 

i have the same rattle as Samcs06,
I'm at 45k, I'm using 93 or 91 oct gas. i did seafoam one year ago at around 37k miles. and I'm using Eneos oil in transmission.
I have no idea what causing that noise.

 

Run the highest prem gas to make sure. Record the sound and post it here. Could be lots of things.

 

the best fuel injector stuff is prestone full syn with boost in it i still have some of the RP and will put it back in and will try to get the sound for you guys but all i ask is if you guys could help me get it on here i dont know how all have done on here is post and read

 

We need a de-carbon cleaner like Seafoam($8 Walmart).