Mazda Rotary Club

General => General Technical => Anything Engine/Performance/Tuning related => Topic started by: Blitz on January 16, 2005, 01:17:05 PM

Title: Engine noises
Post by: Blitz on January 16, 2005, 01:17:05 PM
Can anybody take a listen to this and tell me what that funny sound is when I put my foot off the gas (when its nearing its idle rpm)? And please tell me if I should be worried as well, \'cuz I am.

here it is (http://www.icedesign.org/xternal/Mov01124.mpg)
Title: Engine noises
Post by: asp on January 16, 2005, 01:53:25 PM
sorry aint got a clue,
thats a funny drumin sound,sounds reallly dodgey 2 me, i wouldnt rev it like that till u no what it is,
some 1 will hear it n no what it is thou,
Title: Engine noises
Post by: Ows on January 16, 2005, 01:56:01 PM
Sound like one of the pipes the the airbox has been left off, or have you got the airpump for the cat on with no cat in place???
Just a thought
Title: Engine noises
Post by: Blitz on January 16, 2005, 02:13:32 PM
have a look
Title: Engine noises
Post by: SCOOMER on January 16, 2005, 02:33:45 PM
Mine sounded like that after i fitted the HKS intake.

Think you mite have to live with the TURKEY sound!

Scott
Title: Engine noises
Post by: Ows on January 16, 2005, 02:57:17 PM
Have you got a decat mid pipe.
Title: Engine noises
Post by: gavin on January 16, 2005, 03:07:16 PM
:rollin  sounds like your cars got wind :D
could it be the wastegate :confused:
Title: Engine noises
Post by: SCOOMER on January 16, 2005, 03:07:56 PM
looking at your engine bay it looks like your missing a pipe that gos to atmosphere, think its their to dampen the sound abit, but if you dont have it your going to notice that turkey sound even more!

Heres some pics that mite help.

Scott
Title: Engine noises
Post by: Ows on January 16, 2005, 03:08:17 PM
If you have a mid pipe try disconnecting the airpump (think its the airpump??) and see if that makes a differance.
Title: Engine noises
Post by: SCOOMER on January 16, 2005, 03:09:35 PM
Heres the pipe it looks like your missing!
Title: Engine noises
Post by: SCOOMER on January 16, 2005, 03:12:40 PM
Heres where the pipe should be connected and left to atmos!
Title: Engine noises
Post by: Blitz on January 16, 2005, 06:12:27 PM
I don\'t think I have a decat. Don\'t know actually but the exhaust ísn\'t that loud. Can\'t see underneath cuz its 30mm lowered.

I believe that could be it scoomer. I have noticed a loose hose near where the intakepipe goes down to the turbo, but it looks properly closed (or intented to be like it is now). Will have a go at the air pump as well.

Another thought: I might come from the fact it wasn\'t warmed up yet. The dutch rx-7 owners club already yelled at me I shouldn\'t rev like that on a cold engine :rolleyes:
Title: Engine noises
Post by: Spotlamp on January 20, 2005, 01:19:57 PM
I reckon it\'s your air pump clutch mechanism.  I don\'t think it\'s the pipe running to the exhaust as mine\'s missing and doesn\'t make this noise, it sounds as though it\'s when the air pump clutch is engaging, I think this might be your problem...

HTH
H
Title: Engine noises
Post by: grinder on January 20, 2005, 01:41:19 PM
ha ha ha thats superb !

i have heard of this before - and im sure its something to do with the air pump - not sure though

see if you can PM Phil Bateman - im 100% sure his did the same when he changed the air box

( what a cool noise though )
Title: Engine noises
Post by: bobster on January 20, 2005, 06:19:41 PM
Scoomer is right.

The Pig that is in the engine bay breathes out through that pipe that you don\'t have.
There is a pipe that comes from the back, under the plenum. It usually goes into the airbox and is vented away to the ground. That pipe that scoomer highlighted should connect to that pipe and then vent away to the ground.
Without the little inline baffle it might still sound like a pig.

Mine made the same noise when I broke the hose loose from the original airbox. Was fun for a very short while.
Title: Engine noises
Post by: Blitz on January 20, 2005, 07:04:06 PM
I haven\'t looked at it last few days though, will try to fix it in the weekend. Just to be sure, this issue isn\'t bad for the engine right?
Title: Engine noises
Post by: Ows on January 20, 2005, 08:06:36 PM
Mine does not make that noise and I have about a million or so pipes not going to anything
Title: Engine noises
Post by: Ows on January 20, 2005, 08:08:35 PM
Try and disconnect that clip I said in a post before, will only take 2 secs just to try