Air sucking/swooshing sound need help.

[Mosemy]

I’ve been searching for an answer to this issue for a while no one can see to help to me. I’ll start from the top. Have a 2002 a4 b6 1.8tq5speed. I bought it stock, did and apr stage 1 tune and thats when the sound started. Issue:
When I accelerate I hear a loud whooshing sound in the front passenger side.
It sounds almost like an airbox leak, but it is the wrong side, it sounds like air rushing through a pipe or baffle.
It follows acceleration, I can be in the higher RPMs but not accelerating and I don't hear it. As soon as I accelerate I hear it (builds for maybe a second, the full noise). As soon as I ease and stop accelerating it stops.
It only seems to happen under turbo load. When I test it in the garage I cannot make it happen. Likewise on the road with with the clutch depressed, I can rev to the top of the powerband and not encounter it.
I had the car checked out by my APR installer/audi mechanic. Everything was fine. He heard the sound when he test drove it, said he had never heard it before and had not idea what it was. After checking all my turbo hoses inner cooler hoses and what not he couldn’t figure it out and suggested that i just live with it.
Since then I have installed a 034 testpipe, a evolution race works inner cooler, new apr diverter valve, a full exhaust system and a brand spanking new K04 turbo. As well as the k04 apr tune. Still have the sound. I feel as though I am losing power. But I still get boost and decent pull. But its lacking I had the car on the dyno and it was running slightly lean. Everything seems to be working but it won’t stop i hear it everywhere i go. Its really loud not just the turbo spooling up something more. Any ideas out there?

[MacFady]

How loud/noticeable is the sound? You hear it over your exhaust? I had a hose pop of my intake manifold shortly after I had my stage 1 tune, sounds very much the same as you describe but I had almost no power and the car sounded terrible at idle. Needless to say a hose clamp fixed that immediately but the car was basically undrivable otherwise.

Confused when you say the sound is the passanger side but that is the wrong side for the airbox? Do you mean the sound is drivers side?

[coowhip]

The passenger side is where the airbox is. I would def check all your clamps for the intercooler/DV. Check all small vacuum/boost lines as it sounds like you may have a slight leak somewhere when it's under boost which may not be noticeable with a visual inspection. What psi are you peaking at, and what are you holding at in WOT?

Boost leak test is probably the appropriate way to test for leaks. A few DIY's out there for that.

[userbob0001]

I have something similar. I always thought it was just the sound of the turbo spooling. I noticed it first when my TIP popped off, again when I got my stg1 tune, and it got louder when I got an AEM filter and took the foam silencer out of the airbox. Did it change at all with the test pipe install?

[coowhip]

Turbo spool will be more pronounced as you eliminate restriction such as the TP, TIP, FMIC, DV, and factory airbox/filter.

[CyberPMG]

If you're getting on boost, you're probably hearing the turbo spooling. In stock mode, it's only doing at most 7-9 psi. With the Stage 1 chip, that boost will now spike to around 21 psi and hold around 18 psi.

If you're hearing the noise all the time (when not in boost), then you may either have a broken/loose vacuum line or a crack in the airbox.

I'm guessing it's more of hearing the turbo wake up for the first time with more boost.

[ECS Tuning-Audi]

If your mechanic went over everything and said all your hoses and lines are fine and your car runs fine its just the sound your turbo makes. The fins on the K04 are slightly different than a K03 and you're running almost double the boost. You're moving much more air now so its going to be louder. The fact that you say you hear it only under turbo load makes perfect sense because that's when the turbo would be spooling.

If you're still unsure do a boost leak test to confirm your intake system is completely sealed. Are you still running a stock exhaust/downpipe? Check your flex section there might be a crack or a small hole.

Jason

[Mosemy]

How loud/noticeable is the sound? You hear it over your exhaust? I had a hose pop of my intake manifold shortly after I had my stage 1 tune, sounds very much the same as you describe but I had almost no power and the car sounded terrible at idle. Needless to say a hose clamp fixed that immediately but the car was basically undrivable otherwise.

Confused when you say the sound is the passanger side but that is the wrong side for the airbox? Do you mean the sound is drivers side?

Yes sorry I meant to say I hear it on the drivers side.

[old guy]

Have you performed a boost pressure test yet? If not, you should. I suspect you will find a leak somewhere. If the noise is coming from the drivers side I doubt it is from the turbo, DV, exhaust, intercooler connections, etc. But from your description it is definitely related to boost pressure. So that leaves several hoses and check valves on the drivers side of the motor. You replaced the intercooler so that gets eliminated. Focus on anything connecting to the intake manifold. You can systematically clamp off each hose connecting to the intake manifold one at a time to see if you can eliminate the noise. Quick and easy with a Lisle clamp or similar.

Once you determine which connection is causing the problem it should be relatively simple to trace down the line and find the offending component.

[coowhip]

I had a whooshing sound when I had a vacuum/boost line fail. The one that did was an L shaped line that ran parallel to the end tank of the intake manifold. It's the first one that is visible and connects right next to the IAT sensor. Also want to check or even replace the SJP just because it will fail eventually...just a matter of time.

All my previous suggestions were based off passenger side issues.

[EBG 18T]

What is your vacuum at idle? Post up a requested vs actual boost log.

[Mosemy]

It was a cracked vacuum line the comes off the throttle body. Missed it the first 300 times I looked at my hoses. Finally got my power back! The power I spent so much money on and time on. Thank you all for the input.

[nick91]

Hey guys I have had as well a loud wooshing noise coming from my car it doesn't if I'm in gear or neutral so its not anything to do with boost but it sounds ridiculous. My downpipe flange is coming apart pretty bad anyone think that's the problem? No loss of power just a really annoying air noise its been like this for months plan on getting nee downpipe soon and hop it fixes problem. Anyone feel free to chime in really wanna get this fixed

[nick91]

To correct it "does" when in gear or neutral. But please someone help I have read massive forums and this is the closest one I found to my problem

[old guy]

Hey guys I have had as well a loud wooshing noise coming from my car it doesn't if I'm in gear or neutral so its not anything to do with boost but it sounds ridiculous. My downpipe flange is coming apart pretty bad anyone think that's the problem? No loss of power just a really annoying air noise its been like this for months plan on getting nee downpipe soon and hop it fixes problem. Anyone feel free to chime in really wanna get this fixed

If it does it all the time, even at idle, it sounds like you are experiencing an exhaust leak.

[nick91]

That's what I figured wasn't sure tho cause she doesnt sound any louder than before gonna new downpipe and hope to fix the problem

[diagnosticator]

I agree with the prior posted comments that the noise is caused by the APR tune. My Avant makes the same sound when I am running the APR stage 1 tune. I don't hear the noise when running the stock ECU tune. It's normal considering the APR tune is boosting about twice as much as the stock tune.

[Mosemy]

I agree with the prior posted comments that the noise is caused by the APR tune. My Avant makes the same sound when I am running the APR stage 1 tune. I don't hear the noise when running the stock ECU tune. It's normal considering the APR tune is boosting about twice as much as the stock tune.

This thread is done, Problem was solved. Cracked vacuum line.