Jump to content
SAU Community

Is My Stock Turbo Dying?

Fly_With_Sky
 Share

Recommended Posts

Fly_With_Sky Rising Star

Fly_With_Sky

Posted
Posted

hey

my car is a series 1 r33 gts25t. Lately my turbo has been making a very faint whining noise every every now and then. This happens between -30cmHg and -20cmHg (read out on blitz dual sbc spec s). This is the only time i hear this noise (under very light throttle), never when making positive boost or under hard/harder acceleration.

Is my turbo on the way out? Or is a maybe a slight leak somewhere, or possibly something else?

I've searched some other posts and people say they get a squeal/whine noise when making boost at say 3500rpm, yet i get a faint whine at about 1800rpm, so i'm not too sure...

Link to comment
https://www.sau.com.au/forums/topic/123089-is-my-stock-turbo-dying/
Share on other sites
Fly_With_Sky Rising Star

Fly_With_Sky

Posted
  • Author
Posted

no, it doesn't blow any smoke (looked for that, and have also looked for any oil coming out of the turbo or piping and there is none).

the car has done about 104000km (assuming if it has been wound back, then more than this figure). It is a 93 model.

boost is stock and a setting at 10-11psi. But before the ebc (about 1 and 1/2 yrs ago) who knows what it could have spiked to during the period after the exhaust was fitted, as all i had to go by was the stock boost gauge.

anthonymcgrath Collaborator

anthonymcgrath

Posted
Posted

mine does the same on slight acceleration - changed oil regularly and all seems fine tho - still makes slight whine (like a dog whistle almost) which I've heard on lots of others - bear in mind this turbo is spooling up to the phenomenal speeds it spins at just before the actuator opens so on slight accel your gonna hear something spin up - I haven't heard a totally silent one yet myself but I'm no expert either so every skyline I've driven or drove in might have been knackered lol!

mad082 Grand Master

mad082

Posted
Posted

the slight noise you could be hearing could be air passing through the bov. there is a point where you can hold the throttle where the bov will be open slightly. and since there is air permanently leaking around the bov through a recirculation hole, it can cause a whistle.

anthonymcgrath Collaborator

anthonymcgrath

Posted
Posted

hey mad082 - you mention a bov (I'm assuming thats a blow off valve heh!) - do all r33gtst's have them or are they aftermarket addition?

I only ask as mine too makes this subtle whistle and it is at a certain point on the throttle as you said but I dont have an aftermarket dump valve on my car :D

anthonymcgrath Collaborator

anthonymcgrath

Posted
Posted

theres other signs that your turbo is going anyhow - small puddles of oil in that metal piping that feeds up from your intercooler. There can be slight smears in the pipe that you can wipe of with your finger (charge pipe is it?) so dont fret if you pull it off and see that but if you pull if off and see it dripping then I'd be a bit more worried :D

smoke out the back on hard boost - basically oil escaping I think.

only know this as I had to disconnect mine getting to the spark plugs and we checked this area recently

mad082 Grand Master

mad082

Posted
Posted

all 33's came stock with a blow off valve... although the correct name is compressor bypass valve. it is situated just before the throttle body, on the cabin side of the piping. the are hooked back up to the intake between the air filter and the turbo, so that when you lift off the throttle the air goes back through the turbo to keep it spinning (like blowing on a kids windmill that you get from fair).

mad082 Grand Master

mad082

Posted
Posted (edited)

also i had oil dripping out of my intercooler piping at the throttle body, and a small amount through the piping before i did my frount mount. I thought it might've been the turbo on the way out, but after a few weeks with the front mount i pulled one of the new pipes off and there was no trace of oil at all. it turns out that the stock front seal on the turbo will always leak a tiny amount of oil. the front seal is like a piston ring. it isn't a full circle. it has a slight gap in it.

so my problem was just old oil, and a bit of blow by.

Edited by mad082
Fly_With_Sky Rising Star

Fly_With_Sky

Posted
  • Author
Posted

thanks guys. I will get the car on a hoist and a have a good look to check for tiny leaks in intercooler piping, as well as make sure the bolts on the tubo aren't loose.

Didn't think of the that tiny air recircualtion hole in stock bov, could be that.

Cheers...

Bass Junky Grand Master

Bass Junky

Posted
Posted

Don't discount the bearings.

Mine had that whine on boost, it was on and off, and didn't really effect the performance.

I did a track day at Winton, all was good, but on the video, I coul hear it whining. high pitched noise.

A week later the bearings shat themselves.

So I got a high flow.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Kapr
      RB20DE NEO smallbox clutch.

      By Kapr · Posted

      For once a good news  It needed to be adjusted by that one nut and it is ok  At least something was easy But thank you very much for help. But a small issue is now(gearbox) that when the car is stationary you can hear "clinking" from gearbox so some of the bearing is 100% not that happy... It goes away once you push clutch so it is 100% gearbox. Just if you know...what that bearing could be? It sounding like "spun bearing" but it is louder.
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      Yeah, that's fine**. But the numbers you came up with are just wrong. Try it for yourself. Put in any voltage from the possible range and see what result you get. You get nonsense. ** When I say "fine", I mean, it's still shit. The very simple linear formula (slope & intercept) is shit for a sensor with a non-linear response. This is the curve, from your data above. Look at the CURVE! It's only really linear between about 30 and 90 °C. And if you used only that range to define a curve, it would be great. But you would go more and more wrong as you went to higher temps. And that is why the slope & intercept found when you use 50 and 150 as the end points is so bad halfway between those points. The real curve is a long way below the linear curve which just zips straight between the end points, like this one. You could probably use the same slope and a lower intercept, to move that straight line down, and spread the error out. But you would 5-10°C off in a lot of places. You'd need to say what temperature range you really wanted to be most right - say, 100 to 130, and plop the line closest to teh real curve in that region, which would make it quite wrong down at the lower temperatures. Let me just say that HPTuners are not being realistic in only allowing for a simple linear curve. 
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      I feel I should re-iterate. The above picture is the only option available in the software and the blurb from HP Tuners I quoted earlier is the only way to add data to it and that's the description they offer as to how to figure it out. The only fields available is the blank box after (Input/ ) and the box right before = Output. Those are the only numbers that can be entered.
    • GTSBoy
      Mistakes were made, my R34 Story

      By GTSBoy · Posted

      No, your formula is arse backwards. Mine is totally different to yours, and is the one I said was bang on at 50 and 150. I'll put your data into Excel (actually it already is, chart it and fit a linear fit to it, aiming to make it evenly wrong across the whole span. But not now. Other things to do first.
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      God damnit. The only option I actually have in the software is the one that is screenshotted. I am glad that I at least got it right... for those two points. Would it actually change anything if I chose/used 80C and 120C as the two points instead? My brain wants to imagine the formula put into HPtuners would be the same equation, otherwise none of this makes sense to me, unless: 1) The formula you put into VCM Scanner/HPTuners is always linear 2) The two points/input pairs are only arbitrary to choose (as the documentation implies) IF the actual scaling of the sensor is linear. then 3) If the scaling is not linear, the two points you choose matter a great deal, because the formula will draw a line between those two points only.
×
×
  • Create New...