High Pitch Hiss at idle
 

I just noticed a very high pitched "hissing" coming from my motor at a idle , anyone else have that or know what could be causing it ? The car starts fine, runs fine, idles fine . Sounds like a vacuum leak maybe , but I couldn't see anything disconnected . Had the car for three weeks and never noticed it till just now . Thanks ! DrR

I have had that before...and a rattle that soungs like dice in a yahtzee cup. My hiss turned out to be nothing...just a bypass hose on the intake plenum (top, center of engine, left side of hose after MAF). Mine went away with the extremely hot weather.


AT

Thanks Atacdad , the sound was coming from right by the intake . I'm going in tomorrow for some service , so I'll ask them too ! Thanks again ! DrR

What grade of gas are you using..?

I'm using Shell V-Power ...BUT , the shitty thing is ....here it is on 90 octane

I hear that its normal.

I never had a problem until I installed my Exhaust.

It's a whistle.

I checked it out today and it sure sounds like the alternator bearing.

I'll have to examine it more and use a screwdriver and check all the hoses.

does it stop if you push the clutch in? probably a throwout bearing, but its normal as mine does it too. ive actually had a few serious car guys listen to it, and theyre not 100% positive but all agreed it was probably the throwout bearing

The throwout bearing noise is more of a humming, vibrating noise not a hissing sound like air escaping.

Keep in mind the catalyst also makes a sort of "hissing noise" Open your door sometime when you're idling and lean over and you can easily hear the catalyst. Nothing to be concerned about.

mine hisses like CRAZY
I have been told over and over its normal

It's normal. It is either the air bleed for the oil injectors or jet air nozzles that are in the primary intake ports. They both use a metered vacuum leak. You can easily verify by temporarily pinching off the air hoses that are attached to the intake air boot between the MAF & throttle valve, while the engine is idling. One of the three air hoses will not change the noise, that is for the crankcase breather.

Ok, glad its normal , just never noticed it before ...freaked me out !

I can't hear these types of sounds. Occasionally, I enjoy the "benefits" of having had my ears hammered by howitzers, M-16's, etc. Most think they're immune to this when they're young, but find out different as the years pass (please turn down the volume).

1.3L

Mazda Repair Information

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WHINE OR SQUEAL NOISE FROM ENGINE AT IDLE
Applicable Models
Model Starting S/N Ending S/N
2004 RX8 00000000 ZZZZZZZZ

Some customers may complain of a high-pitched whine or squeal noise fromthe engine at an idle. The noise can be eliminated by raising the engineRPM slightly above idle. This is most likely caused by the primary port jet air nozzles and / or the metering oil pump air ports. The jet air nozzles are located in the primary port of each rotor. The jet air flow is acheived by using air flow from an area prior to the throttle plate. The metering oil injection nozzles also use this airflow prior to the throttle plate to assist oil flow into the engine. This creates a metered vacuum leak into the engine and may cause a high pitched whine at idle. This noise is considered to be a normal characteristic of the RENESIS rotary engine. Use the procedure outlined in the repair instructions to confirm noise is from the jet air or metering oil pump nozzles. 1.Confirm noise. 2.Remove engine cover. 3.Locate both air supply hoses for jet air nozzles and metering oil pump nozzles. Hoses are attached to the air duct located between the MAF and throttle body. Disregard hose that attaches to the oil filler tube4.Confirm noise is caused by jet air or metering oil pump nozzles by temporarily pinching off air supply hoses using pliers. 5.No repairs should be attempted if noise is reduced or eliminated.

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hi guys... i recently noticed that my engine also started making this high pitched whistle too. initially, it was a bit intermittent, so i left it alone. today, it seemed fairly consistent though. so, i let the car idle for a while and listened. and, i was perplexed by it, so i decided to search the site and am happy to have found this thread.

so, based on what i've read here, am i correct to assume it's perfectly normal and safe to ignore? thanks guys. :)

yep,
mine does it every now and then..

beers :beer:

DrRockin' thats definitely normal, i had the same thing, but it wasn't too loud and i asked the dealer, and my mechanic whose done rotary work for years, said its the alternator bearing. so nothing to worry about

ive noticed this noise as well. ive also noticed, when you turn the ignition off, just before the engine stops turning, it becomes more prononced. anyone else notice this?

Havent noticed it happening to my 8.

you'll be able to hear it more distinctly with aftermarket intakes than the stock intake, but all our cars are capable of making the noise. It's usually the jet air tubes.

Here's mine making it:

http://video.google.com/videoplay?do...65511031036891

Here's when i was basically stock. Not even a slight hint of it:

http://video.google.com/videoplay?do...03361395611185

Why I sold mine...
 

This is exactly why I sold my Rx8..

I was hearing a new noise every week ! Dealer always said 'thats normal'

I have a 95 ford aspire with 150,000 miles that runs smoother and quieter than the RX8 did...At least you can feel good sitting in your good looking noise maker !!

okay mine does this when u are driving around 3000-4000 rpms and u try to accelerate a bit first you hear a shhhhhhhhh sound and then it goes away when u add more gas..... it sounded like the exhaust shield vibrated or something a very metallic sound is this what u guys are talking about

If I wanted a whistler, I would have gotten a bird. If I wanted a hisser, I would have gotten a snake. LOL Hope it's normal. Look forward to your response.

ok, so i took the car out today, and this sound is so loud. i dunno if its just my car but its a very distinct and loud "eeeeeeeeeee" sound. i only hear it at idle, or very low rpm. maybe i should record it and post it?