2002 wrx loud whistle help

[glen86]

Hey guys, im new to subarus and just brought a nice 2002 wrx.

Im stoked with the car and it goes well its all stock at the moment. I do have one issue with it though when you plant your foot down and hit 9psi and above of boost i get this loud whistle noise. It drives me nuts and it really loud im hoping its not the turbo on its way out. i done a leak test and i cant find any leaks that would cause it maybe im missing something here.

also theres no black soot to indicate a exhaust leak so im stumped at this point the car reaches target boost fine 13.5psi but this whistle is doing my head in im going to get a video of this happening and post it here.

Any help would be awesome im sure there some pros on here who can give me some good advice. Cheers

[glen86]

heres a video of the whistle

[Kiwi_Fozze]

to me it sounds like a leak, it\'ll be hitting your target, as that\'s what the ecu tries to do, but there may still be a small leak going on.

possibly the recirc valve packing up?

[glen86]

ok ive been thinkin thats a possible cause i did a leak test up to 16psi and couldnt find anything. the car has only done 106000km so im hoping its not the turbo. So how would i go about checking the recirc valve to see if it is packing up?

[Kiwi_Fozze]

swap a known good one in?

[glen86]

The car is completely standard except ive taken the resonator out of the front fender to give it a bit more noise does sound nice now just the whistle is annoying and its been there since i brought the car.

[glen86]

uhm unsure if its induction noise as it whistled before i took the resonator out, it is louder now but thats understandable since the resonator is now out. I think ill try swapping the recirc valve over then if that doesn\'t fix it ill take to somewhere to get looked at.

[Marky]

To me it sounds for all the world like a shagged turbro

Sounds identical to the smoky old previa diesel turbo my neighbours have

[glen86]

Yeah i do think its a buggered turbo im not getting any smoke though. Ive been told by a subaru dimantler that it may be that one of the fins on the comp wheel are bent or chipped im tempted to bite the bullet and get a new turbo can get one this week at a good price.

[BD5_RS]

How did you perform the leak test? Does sound like leak in the intake area - leaking intercooler/piping/bov or perhaps MAF-turbo inlet pipe. It may be a split pipe that only opens under 10psi boost. As previously said it\'ll still hit full boost, but the turbo will be spinning faster to provide air for the engine and the leak.

I had a stuffed turbo inlet pipe which caused a bent/cracked fin on the compressor wheel of the turbo, but that made more of a whine than the hissing type noise you have.

[glen86]

I built a fitting that i put into the rubber elbow connected to the air box. the fitting has a Tyre valve in it and i use a compressor to fill the intake tract with air up to 16psi. it also has a another pipe to blow smoke into so you can see the leaks, it works a treat i found a crack in the rubber hose that goes to the wastegate so now thats fixed at least.

[Pappu1]

is ur blow off tightened correctly

all the hoses tight?

does sound like a leak on boost

1 - start by re tightening all hoses and vac lines and blow off

2 - if still issue - swap blow off and try again

try that and report back

what area u in?

[glen86]

yes all of above have been done ive had it apart 4 times now so everything is tight clamps have been replaced. Have ordered a new bpv so heres hoping its a leaky oem valve.

[glen86]

located in upperhutt - wellington

To me hard to say what it sounds like im told it sounds like a leak but as im a noob to turbo cars im racking my brain to figure out what it is. Definitely a hissing whistle sound which leads me to believe its a leak but still unsure??

[tebbyj]

If the turbo was gone it would happen all of the time that your on boost not just when you get to 10 pounds. Plus car is standard and with low ks so i think turbo will be fine.

Either intake or exhaust leak me thinks. Seeing as youve checked intake and held okay, Get car up in the air running block the exhaust (for 30 seconds to 1 min only at a time) see if it makes the sound then.

[glen86]

Cool sounds like a plan i didnt see any black soot but you never know. Cheers for the advice

[tebbyj]

 glen86 said:

Cool sounds like a plan i didnt see any black soot but you never know. Cheers for the advice

You may need a helping hand as it mite be in up pipe or or manifolds cant be at back and front of car at same time lol

Its not a leak at the gauge or gauge line is it? Has been known to happen as well haha

[glen86]

Not at the gauge whistled before i put it in but yeah ill get my mate to block the exhaust and go from there

[glen86]

ok installed new plumb back bpv sounds great but still have the whistle so this weekend gonna do another boost leak test maybe ive missed something?? then going to take all the heat shields off the exhaust and block the bugger up and see if it a leak there. If all of that doesnt work the turbo is coming out to be inspected this is driving me crazy at this point lol

[ra555]

I had that issue diagnosd myself an found it was the intercooler.( where the y pipes join to th top mount one bolt was missing .replaced the bolt an tightened an whistle went away

[glen86]

intercooler seems fine bolts are all there just weird cause i only get the noise after hitting 9-10psi of boost seems like a leak been checking vac lines again tonight just trying to rule out every possible reason for the whistle/hissing

[Johnnynz]

Did you use a fresh gasket on the BOV? Also did you put a little oil on it to help the seal?

Sounds exactly like my leaky BOV Gasket I had during my IC conversion.

[ra555]

You no its the bolts underneath the intercooler an make sure ther tight

[glen86]

yup new gasket on bpv didnt use oil to help seal and yup had intercooler out at least 4 times now checked all seals on it car runs fine still this dam noise though drives me nuts im gonna figure it out one way or another lol

[Johnnynz]

 glen86 said:

yup new gasket on bpv didnt use oil to help seal and yup had intercooler out at least 4 times now checked all seals on it car runs fine still this dam noise though drives me nuts im gonna figure it out one way or another lol

For the hassle of removing two bolts and refitting it might be worth putting a little oil on it and see if it makes a difference.