Air leak test question
Thread Starter
Pro
Joined: Oct 2010
Posts: 512
Likes: 0
From: Anniston Alabama
Air leak test question
I have an air leak from what I can tell by ear coming from the throttle body on my way '89. I had the fuel system cleaned out couple of months ago, part of that was them swabbing out the throttle body. It ran great for awhile but that's about when I noticed the whistling noise, sometimes the noise goes away for a few minutes. Any ideas? Thanks for your time.
Instructor
Joined: Dec 2011
Posts: 105
Likes: 0
From: El Paso TX
A spray of carb cleaner or throttle body cleaner (during idle) near the whistling sound will verify the air leak. If the idle changes there is a leak. If I had to guess I would say the intake boot is not installed properly and rolled under at the bottom, just a guess.
Drifting
Joined: Jun 2010
Posts: 1,853
Likes: 8
From: Westerly RI
With the engine running, look for cracked or disconnected vacuum hoses. You can feel all around on them where you can't see, and if you touch a leak, you will hear the sound change. Did the noise start just after the work, or did it develop some time later?
Drifting
Joined: Jun 2010
Posts: 1,853
Likes: 8
From: Westerly RI
If the intake boot is not on correctly, as stated, it could cause the whistle. But also, if here was a vacuum hose ready to crack, or ready to fall off, just a touch could have affected it. Suggest you do the check I mentioned earlier. Does the car run the same?
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Thread Starter
Pro
Joined: Oct 2010
Posts: 512
Likes: 0
From: Anniston Alabama
OK so I re-tightened the metal band on the intake boot, that got rid of the whistle. Its still making an unfamiliar noise but not noticeable until it gets past 2k rpm. The idle speed is at 7-800 rpm.
I got the car in October and other than the sound of the cooling fan, its been extremely quite under the hood.
I got the car in October and other than the sound of the cooling fan, its been extremely quite under the hood.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
Before I got to the bottom of the thread I was thinking exactly what Agent 86 said. It sounds like the vacuum line that goes to the EGR solenoid (mounted on thermostat housing) is disconnected.
