tonyjms2005

Hi guys


I am looking at how much my 8 is worth, I really don't want to sell but I cant find any garage including Mazda that knows what they are doing with the rotary engine.


My car sounds terrible but no garage can give me a straight answer whether this noise is normal for a rotary. So I am really close to just trading my rx8 in for something else.


Here is a vid: https://www.youtube.com/watch?v=knwZ...ature=youtu.be

Thanks

Antony


Can anyone upload of video of their stock rx8, my makes that noise around 1000 - 3000rpm.

niteshade247

Sounds like your sucking a lot of air or got a bad vaccum leak. It dose sound sick. Any drop in performance or CEL ?

poacherinthezoo

My money is on a vacuum leak (as previously stated). Until you give a bit more background (as per niteshade's request) regarding CELs, performance changes, when this sound started occurring, etc - its hard to give any answers.

nycgps

iTrader: (1)

is your s AT ?

tonyjms2005

Hi Guys
Thanks for the replies, The compression is good and the car run well, except for a rough idle and a few spots were the car seems to hesitate below 3k rpm, the car is manual transmission with the high power engine.

This what I have checked:

New plugs, leads coils

new exhaust manifold (checked and double checked for leaks)


The ssv moves freely
No engine CEL light (I had one popup about a 6 weeks ago saying catalyst reduced efficiency, I cleared this and it hasn't returned).

I took it to mazda where they said the sound is completely normal.

The manifold I fitted is a stainless steel tubular design. After two weeks of being on the car the manifold near the triangular joint has turned blue and orange/gold.
Is this normal? Can anyone with a tubular manifold comment?
I have suspected the cat but it passed the emissions, maybe it is partially clogged?

When I changed the manifold I inspected the cat front end but it seemed intact.

Thanks again

Antony

tonyjms2005

Update.
Its has been pointed out to me that the "genuine" coils fitted to my rx8 are actually oem knock offs.

Lets see what happens when the proper ones arrive.

Antony

niteshade247

That sucks you'll want to check your cat for sure now change or check plugs wires and yes I have a header too and it's all kinds of colors this hapens as it gets hot it's normal.

niteshade247

Did you reattach the air injection to the new header? If not did you put a block off on the header where it's suppost to go? This could be all the air sound we hear. I'm not for sure what the repecautions of running a cat with out the air injection is perhaps some one with more knolage than I can chime in.

tonyjms2005

Reconnected the air pipe. Checked and double checked for leaks. I have ordered new coils hopefully they may improve things

Thanks

Antony

tonyjms2005

Fitted new coils, air filter, clean maf sensor. Wow what a difference when fitting the actual genuine coils! The car goes like a rocket now


I still get the raps sound but not as much. Maybe I but of rasp is normal? Plus I have got a toyosport tublar manifold fitted.


Thanks


Antony

tonyjms2005

Hi
Again Just an update, the cel has come on with a cat efficiency warning P0420.


Could that exhaust noise be an issue with the cat being partially blocked? The airy blowing noise gets worse as I give it more power at a given rpm.


Thanks


Antony

blckninja

iTrader: (1)

I don't see anyone mentioning the air pump, have you checked that to make sure it's not going out?

tonyjms2005

The noise is present also when the engine is warmed up, the air pump only operates when the engine is cold?

I got the cat temperature off my car ecu when I pulled the code. The temp was 867 degrees centigrade at 3500rpm while cruising.

Does this sound high? I know the carpet around the exhaust tunnel gets really warm with the heat from the exhaust.

Thanks

Antony

blckninja

iTrader: (1)

Correct, the air pump is only on when the engine is cold, so since it does it while warm it's something else.

Not sure about temp, but here is something to help you with the code.

tonyjms2005

Thanks for the info, I have checked most of that
I was just on youtube trying to listen to other stock rx8s, I noticed my car does really pop much on the overrun, just make a tinny rasp at the manifold, I think I will take the cat off and inspect it?

Thanks

Antony