Elevenseries11

1994 FD efini all stock twin turbo
So i have this noise coming from the engine bay. It started the day after i replaced the stock suspension with my new coilovers... though im 95% sure it has nothing to do with the noise.
The noise it self is a High pitch whistle/ nails on a chalk board... kinda like if someones brakes where going bad.... the only thing is it happens im idling and rolling... the noise gets drowned out by the engine if i start rev it high enough ... so i think its constant.... its coming from the turbo side of the engine... if i just barely tap the gas it starts to speed up. Its literaly making me go insane while im driving.

schaft

iTrader: (1)

Check for shaft play in ur turbo, I had the same noise from my compressor wheel hitting the housing.

Elevenseries11

Thanks i'll go check .....was it hard to tell where the noise was coming from? cause i back up about 20ft and it so loud, that i feel bad for everyone when i drive by.... but if i put my head down in the engine bay i can barely hear it, at least not well enough to tell where its coming from.

Elevenseries11

if its been going on for less than a week should i be worried?

schaft

iTrader: (1)

Id park ur car in an open area and stand back from it then walk around to see if u can figure out a side, then move closer, I wouldn't be to worried as long as u still have the same power from the car. Check ur drive shaft to see if maybe a heat shield got wedged against it, use a screwdriver ad a stethoscope around the engine bay. But br very careful.

tasty danish

iTrader: (5)

I'd be willing to bed your turbos are taking a dump. I had the turbo on my car make the exact same noise, only it would only do it when it tried to build boost. the bearings in the turbo were totally shot.

If I am correct: Yes be worried. At the very least you'd need new turbos, if you let it go it will effect other areas too.

Brodie121

iTrader: (8)

My guess would be one of the accessory pulleys bearing or idler pulley bearing has gone bad.

Give that a check first.

Elevenseries11

So i cold started the car for the first time this morning.. and pulled out the stop watch.... it takes 11mins.. for that noise to start happening... basically after the high idle warmup stops.. warms up at like 1.3rpm and drops to about 800-900rpm.... so that rules out the the somthing scraping idea almost... i say almost cause warmup = heat= heat cause expansion in metal = something a millionth of a milimeter to touch and make noise....

i dont think its any of the pulleys ... there making there own noises lol...

backed up from the car and made my way closer and its deff coming from the turbo side of the car... (rightseat drive dont wanna confuse anyone) you can hear it through the wheel well, that side of the engine compartment, and underneath the car...
my its somewhere in the back near the flywheel to back left near the second turbo >_< which i can't really get to without yankin a lot of stuff out.

Could i take the downpipe off and touch the hot side of the second turbo? to see if there is play.

RotaryRX-007

To answer your last question, no, removing the downpipe will not let you touch the secondary turbine. You can pull the intake pipe and grab the compressor wheel from under the car and see if it has any play but I don't think the secondary spins at all at idle (unless you are non-sequential and both turbos run in parallel). Because of that, I'd say it's probably the primary turbo. Pull the front intake pipe off and (on a cold/cool engine) grab the compressor wheel nut and pull it and push it back and forth and up and down. It's probably got enough play for the blades to be hitting the housing.

Elevenseries11

Took the entire intake box out and the pipping leading to the first turbo, but there is a small cast iron lookin elbow on the turbo... so i have to reach down through that to just barely touch the turbo fan... it doesn't budge though...

It is sequential still, its all stock... i just can't figure it out.

Somthing that doesn't make noise until its warmed up.. happens during idle.. happens with clutch up or down... happens when i go through all the settings on the air conditioning... only time it doesn't really happen is when i take my foot off the gas for a split second then it will start again.
Pretty much the same time a blow off valvue would fire....

Elevenseries11

mind you my car is a 1994 with 60 thousand miles on it. and at half oil on the dipstick.....

just startn

iTrader: (33)

This sounds so much like a belt haha. just went threw this whole ordeal in a z32 and it was the belt. I flipped the belt around for the heck of it and the noise was gone.

RotaryRX-007

You said the car is all stock? I've never bought one of these cars with an air pump. In that first few minutes it's working hard until the car gets to operating temp, then backs off. You say it doesn't make any noise until after AWS. Might make sense.

Go to your local auto parts store and buy a stethoscope. It's like the one the Doctor uses to listen to your heart but it has a long metal rod instead of a metal pad. Listen around that side of the engine with the scope. Pulley nuts would be the first thing I listen for.

Elevenseries11

The noise has started to go away, its not as loud anymore. I can't hear it while im driving unless i pass a wall or guard rail, somthing for the noise to refract off.