Odd whistle. Help!

[kannon]

Before I go tearing things apart (and dropping the intake manifold yet AGAIN) let me run this by you guys for suggestions.

Back in April, about 20 miles or so after getting off the dyno I noticed what sounds like a whistle coming from the engine at the onset of boost at partial throttle. It happens at exactly 0 atmosphere up through about 4psi.. then stops. This is on a B16a 99 Si with a JRSC w/ stepper pulley.

My first throught was the intake. I removed it and drove, not it.

Second was the bypass.. I tried zip tying it open to see if it was leaking. The odd thing is, with no boost, the same whistle would start to occur as I approach 0 atmospheres... then stop when I hit boost.

Keith at Jackson thinks its my tensioner pulley bearings failing and making odd noises.. but it sounds more like air to me. I think it might be the Hondata intake manifold gasket leaking...

any ideas???

thanks!

[217gsr]

I have a similar "whistle." Let me guess. . . does this whistle only happen when you are at a standstill and are JUST beginning to move? Or does it happen in all the gears, all the time? With the right throttle input, you can avoid it though, right?

I thought that my whistling was also my intake. I think I ruled out a vacuum leak somewhere, only because my boost/vacuum gauge doesn't show any changes (but I don't know if it would).

Anyways, it's irritating, and I'd like to see what your solution is. [img]smile.gif[/img]

<font color="#a62a2a" size="1">[ July 25, 2002 08:08 PM: Message edited by: 217gsr ]</font>

[96IntegraRS]

My throttle body made that weird whistle...

Does it depend on throttle position or pressure?

Chuck

[waveoff]

Mine does the same thing. A loooong time ago on this board I believe it was Shawn at Moss that mentioned the whistling was caused by the position of the bypass valve when transitioning from vacuum to boost. It's a harmless noise and does not indicate impending doom.

[fastfour]

<BLOCKQUOTE><font size=2 face="Verdana, Helvetica, sans-serif">quote:</font><table border="0" width="90%" bgcolor="#333333" cellspacing="1" cellpadding="0"><tr><td width="100%"><table border="0" width="100%" cellspacing="0" cellpadding="2" bgcolor="#FF9900"><tr><td width="100%" bgcolor="#DDDDDD"><font size=2 face="Verdana, Helvetica, sans-serif">Originally posted by waveoff:
Mine does the same thing. A loooong time ago on this board I believe it was Shawn at Moss that mentioned the whistling was caused by the position of the bypass valve when transitioning from vacuum to boost. It's a harmless noise and does not indicate impending doom.</font></td></tr></table></td></tr></table></BLOCKQUOTE>

That is exactly what mine has done from day one. No problems.

[96IntegraRS]

The reason I know it's definitely the throttle body in my case is that it did it before I put the blower in...

Chuck