# Why does my car sound supercharged!



## gts-tom (Jun 14, 2010)

So I went out in the car last night and I started to notice a high pitched noise when the car came on to boost and the pitch gets higher as the boost raises, almost sounded like a supercharger. It dosen't do it when your driving around normaly using little amounts boost but when you give it a boot full it makes the sound. No change in power or performance and the only thing I have changed is I have fitted a hard pipe kit.
Any ideas.....


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## Marky_GTSt (Dec 31, 2005)

Possibly an air leak, maybe the hardpipes are just allowing you to hear the turbo more, or possibly the turbo is worn...


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## R32 Combat (Jan 29, 2004)

Knackered turbo?


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## gts-tom (Jun 14, 2010)

I do hope not I've not had them on there long


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## 400gtr (Sep 20, 2009)

Mine does the same, had everything checked and told all was ok just one of them noise's that let's you know you have a skyline to make you worried unnecessary.


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## SklyaFett (Oct 18, 2005)

If its a gts-t check the exhurst manifold. I had a noise like that when i had a gtst and it was 4 bolts snapped in the head and the manifold had warped a bit. Its a common problem because the manifold is one piece. Check for black soot around the turbo side of the engine.

Hope you sort noise mate


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## gts-tom (Jun 14, 2010)

Sorry it's an R32 GTR. So I've been outside and started taking things to pieces. Taken some of the pipework of to access the turbos. Check the turbo wheels and apart from a tiny movement "up and down" but no "in and out" the wheels are spinning freely so now I'm lost. No excessive oil in the pipes either. If anything on the drive home last night it seem to have nearly gone away. Then I turn to the side and see this.....
















Seems my car was hungry last night and had eaten something! Any debris that was there has gone now and the cowling is re attached if a little damaged. No damage to the rad. Do you think the fan will be ok left as I can still hear a faint wizzing noise or do you think I should change it :thumbsup:


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## Marky_GTSt (Dec 31, 2005)

Nice find....

I would be tempted to clean the edges of the blades up with some sandpaper to smooth them, hopefully that will lessen any noise.


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## gts-tom (Jun 14, 2010)

Yeah thats what I was thinking :thumbsup:


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## bigkev (Mar 2, 2008)

so did it eat the fan shroud? if so, i presume all of the blades are equally affected? if they are then it should be fine to just clean the tips up.

k


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## gts-tom (Jun 14, 2010)

Yep every blade is the same and its only the tops that are affected


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## Chris Wilson (Aug 20, 2001)

Has the viscous coupling seized solid, or started to seize solid? A lot more than stock RPM on the fan sees it deflect the blades forward and touch the shroud. I run my fan solid and it will just brush the shroud when over 8500 engine RPM. Also check engine and rad mounts in case one is moving excessively / has moved relative to the other.


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## V1H (Aug 30, 2001)

guessing also that since you have a shroud fitted to an aftermarket rad, the clearance might be less than on a std rad, a lot of aftermarket rads dispense with the shroud.


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## herman (Apr 1, 2007)

*just seen this*

hi,just seen your thread,i had the same just took alittle alount off all plastic blades and is fine now,good spot though bud.:thumbsup:


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## zamnap (Aug 3, 2011)

maybe the turbo need a service.


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## blue34 (Jul 28, 2005)

check the engine mounts... the engine might be moving under load and allowing the fan to touch somewhere.

Hold hard on brakes with heal on accelerator at say 2k- engage gear and slowly raise clutch while someone looks at engine to see how much it moves - viewing from the side of the car! with nothing in front of the car either..  in case your feet get tangled...


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## adamsaiyad (Aug 23, 2006)

i would put my money on engine mounts as well fans dont move and if it did move its because the engine moved ?


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## gts-tom (Jun 14, 2010)

Yep think I'mgoing to have a look at the mounts as I have heard a knock or 2 when changing gear. The car is still making a little whining noise but nothing like it was. 
Anyone know how hard it is to change engine mounts. Cheers for the advice chaps :thumbsup:


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## adamsaiyad (Aug 23, 2006)

Its not too difficult, but you need a engine hoist and you need to lift one engine mount, then remove then lift the opposite side and replace then go back to the 1st engine mount raise the engine and replace, its not too bad ?
But it needs time and patience and tools .


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## MIKEGTR (Jul 8, 2005)

zamnap said:


> maybe the turbo need a service.



Or maybe it's the fan u piece. 

Can we expect another 45 posts of shyte before u tell us what you're selling?


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## gts-tom (Jun 14, 2010)

Is it not possible to jack one side of the engine replace the mount and then do the same with the other side


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## adamsaiyad (Aug 23, 2006)

it is possible but i remember i had a struggle and have removed and fitted my engine a few times and know that you cant do one and then the other you have to remove one mount and leave it out the drivers side mount if i remember correctly and then leave it out and lower the engine then lift the engine more to the passenger side and then raise it enough to clear the engine mount leg, then replace it and then lower it again then move the hoist more over back to the drivers side then lift and replace and secure all bolts and you are done tricky but it can be done...
But confirm first is it the engine mount ?


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## gts-tom (Jun 14, 2010)

Well I took the fan off tonight and took it out for a quick run to see if it's still making the same noise, guess what it is. Now think it is one or both of the turbos which is a complete slag. I've only done say 1500 miles on them since i put them on. Anyone have any ideas why they would have done this. They have over boosted a couple of times say up to 1.9 bar when I had a boost issue. I had to put in a smaller banjo bolt as the old turbos bolts would not fit. Do you think the smaller diameter feed could have caused oil starvation. The turbos are only oil fed (Greddy T517z)


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## gts-tom (Jun 14, 2010)

Ok a little up date, So I got my turbos rebuilt as they had seen better days, cost me a small fortune. Turbos turned up and all looks goods so I go and fit them. Now I go test the car as I've also done the brakes but the car is still making the same noise straight from the off. It's when the car comes on to higher boost say plus 0.5 bar and then you get a high pitched wizz like a super charger. Now being paranoid I've taken the inlets off to check for movement in the shaft.There is a little movement say 1-2 mm up and down not in and out, should rebuilt turbos have any movement at all, I've only done say 25 miles on them. They have plenty of oil going to them as I asked the company to check the size of the banjo bolts for flow, I've also changed the oil and filter and checked the old oil and filter for contamination but nice and clean. Could an air leak be making this noise. I don't even want to drive the car at the moment as I can't afford for any thing else to break. Any help would be welcome


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## Chris Wilson (Aug 20, 2001)

A boost leak can make a whining noise, depending on where and how the leak err, leaks 

A REALLY thorough and careful check of all intercooler and associated hoses may show a split. I work commercially on various cars, and in particular twin turbo Supras, I have lost count of how many customers come with a low boost problem swearing on everything holy they have checked for damaged or loose IC pipework, yet within half an hour I have a *uggered hose in my hand. You need to remove them, and check them all PROPERLY. Takes time and effort, but your time may well be cheaper than a garage's time if you do it instead of going to the pub or whatever.

Now, I have had my share of trouble with turbo re-conditioners, but USUALLY if a plain bearing turbo cassette is knackered they will be noisy even without making much boost. Radial play of the amount you describe is normal, axial play should be less than 2 or 3 thou inch max.

It's not got none stock blow off valves on it has it? They can leak and make funny noises, if you have them, and can't find any other issues, try blanking them off altogether.


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## gts-tom (Jun 14, 2010)

It has got standard BOV's on it but the noise does seem to be coming from the passenger side. I'll take the pipe work off tomorrow and see what I can find. If it was leaking boost would the boost controller not be picking it up as over boosting. Thanks for the response.


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## Mookistar (Feb 5, 2004)

Have you asked Ron at RK What he thinks it might be?


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## Mookistar (Feb 5, 2004)

Btw, inlet manifold gasget leak?


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## Chris Wilson (Aug 20, 2001)

If it has a boost leak it would probably be UNDER boosting. There are plenty of hoses around the stock BOV valve region that could be causing trouble, plus there's a black plastic irregularly shaped pipe across the front of the car to feed the BOV's I suppose that could be damaged. You could make up bungs and pressurise the whole mess with a foot pump. I am sure a good visual would be enough though.


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## gts-tom (Jun 14, 2010)

Mookistar said:


> Have you asked Ron at RK What he thinks it might be?


Going to go and see Ron next week I think


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## Mookistar (Feb 5, 2004)

As he's on your doorstep you'd be mad not to

Mook


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## gts-tom (Jun 14, 2010)

Chris Wilson said:


> If it has a boost leak it would probably be UNDER boosting. There are plenty of hoses around the stock BOV valve region that could be causing trouble, plus there's a black plastic irregularly shaped pipe across the front of the car to feed the BOV's I suppose that could be damaged. You could make up bungs and pressurise the whole mess with a foot pump. I am sure a good visual would be enough though.


Is it possible to just block off all of that pipe work off that feeds the BOV so all your left with is the intercoller pipework. Surely its just the same as blocking off the BOV's. Would this do any damage


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