*VIDEO* Vacuum Leak Sound from Upper Manifold?

[savegoodautonfg]

if you still aren't sure get a mechanics stethascope and take off the end so that all is on it is earplugs and open ended rubber hoses. this is one of THE BEST ways to diagnose vaccum leaks and such. try running from the TB to the upper inake like this and you should be able to hear that the whistle starts in the throttle body and moves into the upper intake where it is more predominant because of the way the upper intake amplifies it.

**** it, i jsut brought it to my mechanic. i'm done playing with it.

 

[savegoodautonfg]

Well i brought it on thursday to him and got it back 20 mins ago. he can't figure it out. hes a really good mechanic him and his budyd worked on it for 4 hours. did everything possible can't figure it out.

 

[bill302]

i would pull the upper intake off and look for cracks in the lower and upper intakes then check and replace all the vacuum lines under the upper intake....

 

[savegoodautonfg]

Under the upper intake or the ones in the upper intake?

 

[jgfiveoh]

have u tried backing off the throttle set screw and disconnecting the IAB solenoid like i suggested? if not then u def. should at least try it. you might be surprised. this just sounds so much like what i dealt with for about a month. as i mentioned in my post earlier i saw the vid and the sound i hear gives me flashbacks cause it sounds exactly like my engine when i fought this. besides it doesn't hurt to try. let us know if you get any closer.

 

[jgfiveoh]

i also wanted to add that i removed my upper and lower intake 3 times looking for this "vacuum leak, re-gasketed everything, looked for cracks, tried pouring safety solvent over the intake, sprayed w/carb and choke cleaner, sent back my old intake (and had to eat an unecessary $150 because it was "damaged" as summit put it), even took it to my mechanic who also couldn't figure it out. you name it i tried it. sorry to go on and on but i was making a point. if i was in your posish (and the end of my rope) i would at least give it a shot. i mean good even though i repeat myself.

 

[savegoodautonfg]

i also wanted to add that i removed my upper and lower intake 3 times looking for this "vacuum leak, re-gasketed everything, looked for cracks, tried pouring safety solvent over the intake, sprayed w/carb and choke cleaner, sent back my old intake (and had to eat an unecessary $150 because it was "damaged" as summit put it), even took it to my mechanic who also couldn't figure it out. you name it i tried it. sorry to go on and on but i was making a point. if i was in your posish (and the end of my rope) i would at least give it a shot. i mean good even though i repeat myself.

and you never found it?

 

[jgfiveoh]

well i found it alright, and it was just the throttle body whistling, not an actual vaccum leak. assuming all your vac connections are all ok, and i'm sure you've checked them a million times now, i'm thinking you should investigate the TB and IAC. in the video it sounded like the noise started in the TB and was amplified in the upper intake. i also noticed that you can hear the internals of the engine going round pretty clearly. i believe that the throttle plate on your TB is cracked open too much. this not only gives the engine that weird sound but can create low vacuum readings also.

 

[uneverkno]

I think i might have the same problem. Ive checked and checked and checked some more and still cant find it. Its right at the back of the intake. you can hear it over the car while its idling. ive even swapped throttle bodys and still does the same thing. If any of you all figure this out. let me know.

 

[savegoodautonfg]

I think i might have the same problem. Ive checked and checked and checked some more and still cant find it. Its right at the back of the intake. you can hear it over the car while its idling. ive even swapped throttle bodys and still does the same thing. If any of you all figure this out. let me know.

I sent you a pm. write back. thanks man

 

[savegoodautonfg]

did you check the smog line to the back of the heads???

Where are these?

 

[savegoodautonfg]

UPDATE:

I've check PCV Valve, EGR Valve, IAC Motor, All Upper Intake Hoses, everything i can think of and was mentioned here i tried.

when i played with the idle screw i could get the noise to go away but the idle was too low then and it was dieing.

any more ideas anyone?

I can't see it being the Throttle Body, i know BBK Tb's are known for whistles but i never had this problem before.. the TB never whistled until taking off Upper Intake to paint it like mentioned in the beginning of thread

$25.00 reward paypal if someone finds the problem

 

[66sprint6]

its the TB...mine did the same thing and drove me NUTS when i put on the new cobra upper and lower and 70mm TB. I swore I did it wrong and was frustrated to hell then I backed off the idle to get it to at least idle right and it went away...now I only hear it when I am comin from a stop or the RPMs hit around 1k or so. Go swap back to the stock TB and start it up...I garun-frickin-tee itll go away. Like I said, I nearly pulled my hair out and it ended up bein stupid simple.
Matt

 

[savegoodautonfg]

Matt,

thanks for your response. the thing is though their was no noise there when i had it on the first time.. it only started after i took upper intake off though.