Vacuum leak or something else?
 

I just got my 8 back from its first dealer service. In addition to changing the oil and filter, they did the M-flash and the airbag recall work.

I am now hearing a steady whistling sound from somewhere near the top of the engine, perhaps on the back side (it's hard to pinpoint the source). The whistle does not seem to change in pitch when I blip the throttle, and I hear it only when the engine is hot. It's loud enough to hear from inside the car with the doors and windows closed. I detect no change in performance or fuel economy.

I'm no expert, but the first thing I thought of was a vacuum leak. I checked around the top of the engine (with the engine running) but could find no disconnected hoses or tubes. Is there something else I should be checking? Or is the noise perhaps normal? It's been hot here lately, and I've been exercising the car with enthusiasm.

I'll be grateful for any thoughts or tips.

Ted

Hard to say. A vacuum leak, even a minor one, should cause driveability problems.

But, it could be a VERY small pinhole leak in a hose or something.

Heck, if nothing else, get the dealer to look at it.

Dale

With the engine running spray some starting fluid (just a little bit) around the intake system. If you have a vacuum leak then the engine will rev up when the starting fluid is sucked into the engine. If you can use a small tube in the nozzle like from a can of WD40 then you can do this at each tube junction or gasket. If the engine revs increase then that is the source of you leak.

I posted this same problem about a month ago. (high pitch whistle from engine can hear it if you listen carefully with the windows and moon roof closed, I hear it the most in the garage). Took it to the dealer, They said they could hear it. They even compared it to another RX-8, But there response was it would very difficult to find. They felt that if it were a vaccume leak that it would show a fault code. If it makes you feal any better over the last month it has not gotten any worst and there is no effect on performance. If you take your's to the dealer and find something out please bost it. My previous post was "Whistle @ idle"

Thanks very much for your responses and suggestions.

rockin, I'm sorry I missed your previous post in my earlier searches. I'll look it up, and I'll post an update if and when I learn anything new.

mine makes the noise
it drives fine but the noise is there

Has anyone confirmed or come to the conclusion that maybe the dry oil lines, being disscussed in another thread, may have any relation to this. It maybe the same thing just being described differently?

My noise is pretty loud, really noticeable at stop lights and when driving by a wall that reflects the sounds.

Hi - I just noticed this whistle on my '05 MT...started about a week ago at about 11,000 miles...coincident with the temp getting into the 80's here in Richmond.

Anyone discover a cause?

I still have the wistle and it is outside air temp dependent for sure. All winter and no sound at all and as soon as the temp go above 80 and the wistle returns. I really wish we could find the reason for this. The only additional info I have is listen to the engine when you shut it off the wistle sounds like it is spooling down and not smooth like I would guess a vaccume leak would be. Just an idea what do you think?

ac compressor?

Zoom...perhaps you're right....since I got my car in October, this is its 1st summer. I only notice it after coming home at night...75mph cruise for about 15 minutes....w/AC on. I notice the whistle when I pull into the garage. If I restart the car a little while later when it is still hot, the whistle noise is still there. No change in the car otherwise over the 11.5k miles.

For me I already tried with and without the A/C on and the wistle was still there.

pull your a/c fuse and then try it
olddragger

Someone out of his own good will installed a turbo in your car

Bump.

I've got a typhoon intake installed. Yesterday did my own DIY intake tube extension,
found that the VFAD tube was not on. I thought reinstalling the tube got rid of it,
but yes, the engine warm up just brought the sound back again. But it sure does pull
harder with the vfad hose fitted, and fitted a nail the other end as i took the vfad out.

Please notify if anyone finds a solution. Do you guys have an a/market intake?