Police sirin? Turbo noise?
08-01-2003, 02:35 PM
#16
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Here is another link:
http://pcparamedics.netfirms.com/sound.html
Ill check all pipes - - yes... everything is stock
I will have to see if it is chipped or not...
Anyone else that has or knows of this prob??
http://pcparamedics.netfirms.com/sound.html
Ill check all pipes - - yes... everything is stock
I will have to see if it is chipped or not...
Anyone else that has or knows of this prob??
08-01-2003, 04:00 PM
#17
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Sounds like my WRX
It makes almost an identical noise. It's completely normal on the WRX, but maybe Porsche went to greater efforts to isolate the pass compartment from engine noises. It's most noticeable when driving slowly with very small throttle openings.
--Kevin H.
--Kevin H.
08-01-2003, 06:43 PM
#19
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You need to free rev the motor and see if the sound is still there. It sounds like an alternator whine to me. Turbo whine is not diretly proportional to engine speed, especially on deceleration. Since the alternator is dependant on engine RPM, it will follow that falling RPM curve.
Check that out and get back to us.
Check that out and get back to us.
08-01-2003, 08:10 PM
#21
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The K26 at stock boost should be pretty quiet. You have taken off all the rubber boots and checked them for cracks right? Visual inspections are not good enough, you need to message them to see if the cracks appear. Also, check the J-boot, they are known to crack and split at the turbo connection. This will give you an opportunity to check the impellers on the turbo, as well as axial play. After that, if all looks good, check for carbon on the flanges of the exhaust side of the turbo.
Velvet, the K27 compressor is larger and will make more noise. Since you are down on power.. I would think there is something up with your charging system. A ruptured boost could do it, but also a failed open wastegate could as well.
The wuick check for a failed wastegate is to start the car cold, touch the exhaust before the converter until it is hot. Then, touch the dump tube of the wastegate. It should be cold, or barely warm. If it has some pretty good temperature, the wastegate has failed open.
Velvet, the K27 compressor is larger and will make more noise. Since you are down on power.. I would think there is something up with your charging system. A ruptured boost could do it, but also a failed open wastegate could as well.
The wuick check for a failed wastegate is to start the car cold, touch the exhaust before the converter until it is hot. Then, touch the dump tube of the wastegate. It should be cold, or barely warm. If it has some pretty good temperature, the wastegate has failed open.
08-01-2003, 11:05 PM
#22
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"You have taken off all the rubber boots and checked them for cracks right?"
Well no... not yet... because it involves taking alot of stuff out in order to get to them...
I will try this weekend. (It is my only car
)
Well no... not yet... because it involves taking alot of stuff out in order to get to them...
I will try this weekend. (It is my only car
)
08-01-2003, 11:08 PM
#23
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Come to think of it, I remember the same sound on a 931 that I rode in once... It was in pretty bad shape though... Hehe maybe that tells me that my 951 is too... j/k
08-02-2003, 05:52 AM
#24
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So far Velvet and I have the EXACT same problem...
Velvet: Have you checked all your hoses etc...?
I have to do that tomorrow.
Seems like the cause of the noise (if it is the turbo) would be the turbo spinning too fast. The cause of that would be faulty wastegate (or triggering) or leaks in the boots/hoses, right?
Velvet: Have you checked all your hoses etc...?
I have to do that tomorrow.
Seems like the cause of the noise (if it is the turbo) would be the turbo spinning too fast. The cause of that would be faulty wastegate (or triggering) or leaks in the boots/hoses, right?
08-02-2003, 07:41 PM
#25
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I have ripped every fu#$*&! hose off the intake side, TWICE! Nothing, Filled the hoses with water, massaged them, nothing. I really think it's in the exhaust side. I've heard of the doubled walled downpipe off the turbo collapsing. i have to check that. I guess it could be my WG also. That's the next thing. I want my punchy turbo back!!!! By the way, I'm putting Guru's in this weekend, but am currently puttin 253 hp to the pavement... I want more!
08-04-2003, 02:45 AM
#26
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The noise usually happens when under light boost < .75 bar. It goes away at high boost >1 bar. It gets really loud when going up hills when boost is about .5 bar. Does this sound like a wastegate problem or BOV leaking? The strangest part is that it seems to be louder in the cab than in the engine compartment (although my A/C compresser growles really loud possibly drounding out the whine in the engine). Definently boost related...
08-04-2003, 08:37 AM
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I've heard that noise a million times... your turbo is going down.
the noise you hear is clearence in the bearings which will cause movement in the centersection which throws the unit slightly out of balance and makes the noise.
Remove the inlet hose from your turbo and see if you can move the shaft back and forth, then up and down. You should have NO back and forth movement (thrust) and just a slight up and down.
the noise you hear is clearence in the bearings which will cause movement in the centersection which throws the unit slightly out of balance and makes the noise.
Remove the inlet hose from your turbo and see if you can move the shaft back and forth, then up and down. You should have NO back and forth movement (thrust) and just a slight up and down.
08-04-2003, 03:06 PM
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"james bond"
haha okay... had that in my 931 - used to that :P
thanks so much
Chris
P.S. i will check like u said tonight wo see if that is the problem
haha okay... had that in my 931 - used to that :P
thanks so much
Chris
P.S. i will check like u said tonight wo see if that is the problem