Howling noise from turbo and no boost

[220bhp]

My 3B is making a howling noise from the turbo,the turbo is a new RS2 unit,borg warner,resently fitted and has been boosting,untill now that is, the car went into limp mode and this howling noise developed.
I have take all the hoses of and checked each one and they are all ok apart from a bit of oil.Ihave checked the tbv and it is workingand the wasgate diaphram is holding vacume,reset ecu took it for a drive and still the same.Iam wondering if the waste gate could be stuck open if this is possible.

[terrybullwon]

How does it drive?

[AndyP]

When you had the hoses off did you check that the turbo is turning freely and has no play in the shaft?

[220bhp]

The car starts and runs perfectly apart from no boost and this howling noise,I did check the turbo and it spins ok,there is no play from side to side but a little in and out.
I have checked all the vaccum hoses and they all hold.

[Rusty]

If it runs properly then it's unlikely to be a massive inlet leak as a MAF equipped car would throw a wobbler. Exhaust manifold / gasket or EM to turbo gasjet sound quite likely, or a stuck wastegate.

[newsh]

Dv?

[220bhp]

I checked the dv by sucking on the valve and it opens.

[AndyP]

When you say no boost, do you mean nothing at all or it's not getting full boost?

[newsh]

Has it got cats on it?

[Vilhelm]

I had the same problem on my old Audi 100 with 3B. Turns out bits from my manifold were hitting the exhaust side of the turbo, damaging it. I went through 2 turbos, before getting my 3rd turbo with a different manifold.

I would suggest that you take off the DP and examine the blades on the hot side.

[220bhp]

I get a little boost 0.3 or there abouts but the car dos'nt like it and I am reluctant to try as this noise is quite loud which is quite worrying.
The car is decated, and just to exsplain I have resently fitted the following,

RS2 k24 7200 new
oem rs2 exhast manifold, new
rs2 injectors
7a fpr
3bar map and s2 chipped ecu paul n
standard every thing else 3b

The car has done about 450 miles since fitting these items and boost was very good in the begining a little to good as it was over boosting/spike to 2/2.1ing in 4th and 5th
then cutting the boost then climbing and so on,it pulled like a train in first three gears,I have checked the wastegate diaphramby sucking on it and it appears to hold vaccum but could it still get stuck open,if so how do I check this.

[220bhp]

The boost figgers in my previous post are incorrect, I checked just now and I am getting no boost it lifts to .o bar on the gauge, so no boost at all.

[dkw_dude]

Do a pressure test. It can be hard to spot splits in the hoses. If you apply 2 bar boost to standard 3B hoses chances are one or more of them will split. You will get turbo noise from the air escaping also (or from a wrecked turbo .) Wastegate stuck open doesen't happen often afaik, but if you apply some pressure to the wg hose (.5-1 bar or so depending on what wg spring you are running) the wg will open, and you will hear a distinct "clunk" as it closes. Expect a little leak past the wg stem when it opens, thats normal and nothing to worry about.

[220bhp]

I have had all the boost hoses of and inspected them one by one,vaccum also they are samco and are all ok.Also took the cap of the wastegate and it is moving freely and the diaphram is good.As for the turbo Ican turn the shaft on the cold side no problems the howling noise sounds like the turbo spining without pressurizing,I gess the only way to be sure is to tke it of

[GazzaG60]

maybe the howl is the turbo spinning so hard its on the limit.

thats an issue with boost leaks. turbos work hard until its found.

had similar with a subaru once. turbo sounded like it was 2 bar plus for 0.5 bar pressure. half a hose popped off.