A Question For You Turbo Guys.

[Flatline]

My friend is paying off his mom for an 84' Z31 300zx Turbo.
He has no clue what he is ever looking at yet so im helping him.
but my experience with turbo cars is limited.

Right now there is a whine. not a whistle like i have heard from turbos before, but a whine.
sounds like an alternator whine but is definitely coming from the intake.
i know sometimes having a cone filter can do that but taking it off doesn't help.
it runs fine over all with it. but im not sure what could cause it.

the turbo is old. original turbo and the car has just over 98k on it.
Bearing wear maybe? Or could it be a leak in the intake piping?
i have a video of the motor running if anyone thinks it will help.
im not sure how well the sound will show up though.

[turbo90accord]

post the vid cause a whine can come from alot of different thing.

[acchonda]

You could also hit up sites like...
http://www.zdriver.com/forums/forumdisplay.php?f=8
or
http://www.300zxclub.com/

[Flatline]

Here's the video. as you can see, it is definitely coming from the intake

[turbo90accord]

no video there

[Flatline]

Sorry. i forgot to hit paste.

http://s294.photobucket.com/albums/m...t=CIMG2592.flv

there it is.

[brawl]

does the tone change at all when the engine is revved up? Any variances in noise? Does it still whine under load?

[d112crzy]

Holy fuck. Is it really that loud?

Try taking the filter off.

[Clean-CB7]

OMG shit sounds like my vacume lol

[Flatline]

does the tone change at all when the engine is revved up? Any variances in noise? Does it still whine under load?

I haven't had the chance to drive it. his mom is really stingy. yells at people for revving to 3k before shifting and shit. but it does that at idle (700-1200 rpms) but right when i push the throttle it get a little bit quieter, but then right back.

Note: this is all under 2k rpms.

Holy fuck. Is it really that loud?

Try taking the filter off.

Yeah, it's really that loud. Taking the filter off just makes it louder.
My girl called and was literally like "What are you vacuuming?"

OMG shit sounds like my vacume lol

^^^

I told him to get it inspected by a friend at Firestone. $20 for a full vehicle inspection. i figure it'll help him because his momma wants him to change the brake lines because she is convinced the brakes are leaking because the pedal went really low and was spongy. Bled the lines and it's perfect. but whatever it takes to shut her up.

[turbo90accord]

possibly a leaking/fluttering diaphragm on the blow off valve/bypass valve? maybe something caught in the mass air sensor.