MX-3.com

http://www.youtube.com/watch?v=KJXXLnL2jWI

It clatters only at normal operating temperatures. But it is very quiet when cold starting. seems like its comming from the timing cover the loudest..

Could be your timing belt adjuster. Take a screw driver and hold the plastic end to your ear and touch the other end on the engine valve cover. The closer you get to the problem the louder the sound will come throught the screw driver.

Yep, that's the infamous timing belt tensioner rattle. When the tensioner fails it lets the tensioning pulley hit the cover. Mine's doing that too.

Oh I see.. So I just replace that? How much are those things?

lol mine not that bad yet...

$170 at a Canadian dealer.

You can also do this: http://forums.probetalk.com/showthread. ... +tensioner if you don't want to buy a brand new one.

post a wtb. Some people sell theirs for 60 bucks. Like, I would sell mine for 60 bucks if you need one.

I think it could be the hydraulic lifters under the cam cover. It happens on a lot of mazdas. There is an oil additive that you can get to stop the noise in New Zealand but i dont know about elsewhere. It has happened on my car and as soon as I added the oil stuff they stopped rattling.

Thanks all. I read somewhere too that it might be the cam friction gear?

I would most definitely say it's the timing tensioner.

Is this what you are talking about SuperK?=

http://cgi.ebay.com/ebaymotors/TIMING-B ... 0006r26218

No sir, this is it:

http://cgi.ebay.com/ebaymotors/_Car-Tru ... 240%3A1318" onclick="window.open(this.href);return false;

Thanks SuperK.. Wow that looks complicated to change.