Weird noise update
02-29-2008, 06:35 AM
#1
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Weird noise update
Hello everyone. As you may know, I have been investigating a loud humming noise for quite some time. But now I have it narrowed down to three things.
1: Diverter valve - The DV in the car is a two year old 710N, I swapped it out with a two year old 710N from my S4 and the sound is unchanged. So either I need to buy three new DV's or the DV is not the problem.
2: Poorly manufactured APR intake hose. It was a b**** to get on. The n75 and DV are nearly on top of each other. But what might be causing this problem are the flaps or rubbery plastic that stick out where the DV outlet connects to the base of the hose. Maybe this is creating the sound, much like blowing across a stretch piece of plastic bag will. This is not incredibly likely, but it is worth a shot.
3: <deep sigh> Turbo. This shouldn't be the case. But it is the only thing left in the system.
Anyone want to place some bets?
1: Diverter valve - The DV in the car is a two year old 710N, I swapped it out with a two year old 710N from my S4 and the sound is unchanged. So either I need to buy three new DV's or the DV is not the problem.
2: Poorly manufactured APR intake hose. It was a b**** to get on. The n75 and DV are nearly on top of each other. But what might be causing this problem are the flaps or rubbery plastic that stick out where the DV outlet connects to the base of the hose. Maybe this is creating the sound, much like blowing across a stretch piece of plastic bag will. This is not incredibly likely, but it is worth a shot.
3: <deep sigh> Turbo. This shouldn't be the case. But it is the only thing left in the system.
Anyone want to place some bets?
02-29-2008, 07:33 AM
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Hummmm (just kidding). Doen't sound like Turbo. You know, you may be chasing nothing
but a harmonic that has no effect on performance.
For grins, try installing the DV backwards. you might get a performance gain :-)!
For grins, try installing the DV backwards. you might get a performance gain :-)!
02-29-2008, 07:36 AM
#7
Stock style DV's....>
including the 710 seem to have a slight harmonic right at the hg/boost transition point, especially when the car has been modded for more boost. I'd swap in a different style DV and see what you have...
