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AudiNFS
11-11-2010, 01:13 PM
Figured out the videos this time. Not sure if starting a whole new thread was a bad idea or not but oh well. If you listen carefully, there's a hissing sound around 5-8 seconds in the video you. Don't have your volume all the way up as you won't be able to hear it. I ask for help once more with the whole process. Thanks all.

http://s990.photobucket.com/albums/af30/Brooks_Johnson/?action=view&current=20101111155606.mp4

Nateness
11-11-2010, 02:26 PM
Where is your boost gauge?

Diagnosis off of sound doesn't tell us much. Do you feel a loss of power that wasn't normally there?

Boost leak?

AudiNFS
11-11-2010, 02:31 PM
You're very right sorry about that.

I've owned the car for 3-4 months and this sound has been there ever since I've had it. It's a 1998 A4 1.8TQM. At idle, the gauge reads 22-23 In.Hg. In 1st-3rd gears, I boost 6PSI. In 4th-5th gears, I boost 8.

As for power, like I said, i've always had the car like this. I've had my FPR, where my gauge is hooked up, and my line going from the DV to the manifold replaced. I also have Bosch F6DTC spark plugs, and a Forge 007 DV installed.

Nateness
11-11-2010, 02:43 PM
All of those values seem within the typical range for a stock 1.8T.

About when do you see peak boost being made? Is this sound a new symptom to you? Rushing air noise at high rpms on a turbo is fairly normal. Is the noise very high pitched (like a dentist drill?)

If you do observe any differences that can be measured on the boost gauge, then I doubt that you have any mechanical issues.

I recommend that you do not tap the FPR for boost/idle signal. Replace the line and tap the DV line instead.

AudiNFS
11-11-2010, 06:36 PM
This sound is not new. I've had it happening ever since I've owned the car for 4 months. Now that you bring up the dentist drill, it's not that high pitched. It sounds more low pitched than the dentist drill. Like not as much like something's dying. Sounds more like a hissing sort of is the word I can think of.

Either way, I notice peak boost pretty much immediately after I push the gas down above 2K RPM's. I can also hear this sound with the windows up. And it only occurs when I have the gas mashed to the floor, not when I cruise up the the 4-6K range, which is when I hear it when in boost. Never before.

coolgraymemo
11-11-2010, 09:50 PM
have you checked for boost leaks?

Seerlah
11-12-2010, 02:11 AM
Sounds more like you are hearing your turbo spool.

shokwav09
11-12-2010, 08:24 AM
is your clutch slipping?

AudiNFS
11-12-2010, 09:40 AM
is your clutch slipping?

There's no way much clutch is slipping. My car is all stock speed wise and I just had an FX300 w/ LWFW put in. And I also do't really know how to check for boost leaks..

shokwav09
11-12-2010, 10:56 AM
There's no way much clutch is slipping. My car is all stock speed wise and I just had an FX300 w/ LWFW put in. And I also do't really know how to check for boost leaks..

putting in a new clutch doesnt mean it wont slip. and clutchmasters has delivered problems with my clutches in my srt's too. to within thousandths of an inch to be exact. if its got grease or anything on it, itll slip. did you honor the break in? thats usualy a big deal for clutches. trouble shoot. since you dont how to test for leaks. until you do. check the couplings one by one. this would also be a good idea to upgrade over factory couplings and not cost as much in the longrun. from turbo to throttle. torque you mainfolds just in case to factory spec, maybe even check those gaskets if it still permits. hope something of these helps

Watson
11-12-2010, 11:17 AM
Sounds more like you are hearing your turbo spool.

1+

AudiNFS
11-12-2010, 11:43 AM
putting in a new clutch doesnt mean it wont slip. and clutchmasters has delivered problems with my clutches in my srt's too. to within thousandths of an inch to be exact. if its got grease or anything on it, itll slip. did you honor the break in? thats usualy a big deal for clutches. trouble shoot. since you dont how to test for leaks. until you do. check the couplings one by one. this would also be a good idea to upgrade over factory couplings and not cost as much in the longrun. from turbo to throttle. torque you mainfolds just in case to factory spec, maybe even check those gaskets if it still permits. hope something of these helps

I'll look more at this later but thank you. Im in school right now so I can't fully focus.

However, yes I did honor the break in period. I waited till 700 miles of stop and go till I got into boost at all. Also I had a slipping clutch in my car before this one and it's never felt like that slipping OEM clutch since then at all.

AudiNFS
11-12-2010, 11:46 AM
1+

I do hear the turbo spool. And hear it up until the RPM's drown out the turbo sound. I also wanna mention that if my turbo is going and hypothetically it was making the horrid dentist drill sound (even though I don't think it is that sound), why would I only hear the sound at certain RPM's instead of the whole range of the RPM's when the turbo's being used?

Watson
11-12-2010, 12:26 PM
Because a turbo is only at full spool at certain RPM's and your turbo is not in full spool in any of the lower RPM's. I beleive its 4300 when you hit full spool but I am not positive on that.

AudiNFS
11-12-2010, 02:09 PM
Because a turbo is only at full spool at certain RPM's and your turbo is not in full spool in any of the lower RPM's. I beleive its 4300 when you hit full spool but I am not positive on that.

That's pretty much about when I hear this sound too is around 4300 RPM's

shokwav09
11-12-2010, 10:38 PM
That's pretty much about when I hear this sound too is around 4300 RPM's

and when i watched the rpm tach hit 4700 it seemed like it jumped. i just didnt post because i wasnt 100% certain. you guys warch and tell me what you think

AudiNFS
11-13-2010, 05:19 PM
I didn't really see it..

AudiNFS
11-17-2010, 08:23 PM
Anyone?