weird sound on cold start
 

I own an '07 GT with just over 100000 miles and I have about 3000 miles on Mazda Reman. I have noticed in the past week or so that on cold starts I get a weird high pitched sound when idling and it disappears when I push in clutch pedal. I have not noticed any performance changes, just this weird sound that disappears when I push in clutch. I only noticed it happen a couple of times in the past couple of weeks.
Any ideas on what it is? Is there a fix??

Sounds like the clutch release bearing is starting to go. It's included for replacement in clutch kits, and is usually replaced along with the clutch and pilot bearing. Which one of those 3 parts fails first almost doesn't matter, whichever one goes first triggers replacement of all 3.


Keep an eye on your cooling system with that new reman. If you haven't flushed it thoroughly within the last 1,000 miles or so, I'd highly recommend doing that. Lots of cooling systems fail between 5k-10k after reman replacement from all the excess sealant used in reman assembly that then floats through the cooling system until it finds a place to clog something up. Even if you flush, it's possible that you may end up with a thermostat failure or radiator clog, so consider planning on replacing them relatively soon (but not until you flush first)

Thanks RIWWP,
I guess my next purchase is going to be a new clutch kit.
If I just started noticing it, any ideas on how long it will last?

As for the cooling system, I was having problems, so the rad was replaced just recently.
I also had intake cleaned and new SSV installed.

Everything else seemed fine until I started hearing this sound.

That's very hard to judge, but typically it can still last another 5,000-10,000 miles when rattling, possibly longer. You will know when it's definitely shot when the clutch pedal feel changes. Be wary of ignoring it though, as when clutch parts start coming apart at 9,000rpm, random strange damage can occur. I had shrapnel from my exploding clutch disc cut like butter into my starter nose, pinning the starter to the bellhousing, creating a 'locking tab' against the flywheel teeth to keep the engine from turning, and also prevent the starter gear from engaging. I have a thread with pics around somewhere :)

Bingo. I see cooling system failures after reman installs incredibly frequently. Glad you caught it!

Wow.
I will keep this in mind, thanks for the information.
I will be getting it fixed in the near future.

Is it possible that it could be the pilot bushing/bearing? Instead of the throw out bearing? or could it be something as simple as a mal-adjusted clutch?

Yes, it's possible that it is the pilot bearing instead, but not likely. Typically the pilot bearing noise will be always present, and not significantly change when you push in the clutch. It doesn't really matter which one it is though, as they have all of the same replacement procedure except for the very last step, which is almost trivial for each, and you get both in a new clutch kit.

It could be a mal-adjusted clutch if A) you just had a new clutch put in, or B) Your clutch pedal assembly is breaking. If your clutch assembly is fine and you have been driving on the current clutch/bearings for a while, this isn't going to be a clutch adjustment problem

My clutch pedal assembly had broke and was replaced just a few months ago (before I got the reman), but it never felt right since, until this sound started.

I guess it would feel a bit different after having one let go on you.)

I'll be looking into clutch kit options.

Any suggestions?

OEM. Exedy Factory Clutch Kit, RX-8 | Black Halo Racing

It's cheap (comparatively), lasts 80k+, fits perfectly, and has more torque capacity than you can produce naturally aspirated.

Cool, Thanks

This morning temps were around -5 degrees Celsius when I started it up.
It started up no problem but I got the high pitch bearing sound and the rpms bounced from 1500-2500 for about 15 sec.
Is this normal cold weather start behavior or is there something more than the clutch bearing going?
This was the 1st cold weather start since new reman. and intake cleaning/SSV replacement

Yesterday, when I started it up, it did the opposite of last time... Quiet on start and idle and when I pushed in the clutch there was a high pitch sound...
Could this still be the release bearing?