Just buy a smoke tube kit -

here's an example:

http://www.labsafety.com/gastec-smok...-kit_24531933/

More thorough searching will find cheaper ones.

 

Thanks Randy.

 

Why does nobody (to overgeneralize) post their findings and final resolutions?!

New FAQ req'd!

 

This is one thread for which I NEED an answer too.

85 Platinum car. Stan Shaw wintertime rescue a few years ago.

Put 20,000 miles on it. DD Still can't find the whistle.

 

I am searching for it as well.
From what I have read it seems to occur on 85/86's after an upper intake refresh.
I stated before, I wonder if many people opt for the paper, less expensive intake gaskets, rather then the expensive OEM metal gaskets, and that could be causing the problem.

 

I think some have found the whistle to be from tired o-rings in the throttle body shaft. I've not had this issue myself and haven't rebuilt any throttle bodies, so PC-85-928S could be right as I always use the metal gaskets.

 

I used the paper gaskets, no whistle here.

I did replace the O-rings in the throttle body because I had vacuum leaks in it (and everywhere else before the top-end refresh.)

I think it's definitely an unmetered air leak. If you pressurize the entire intake system and it won't hold air, you've got unmetered air going into your system and that could cause a whistle depending on the size of the hole and frequency of the air going through/over it.

 

As stated in the initial post...the ICV whistles at certain openings, depending on the amount of bypass air from the idle screw. Raising or lowering the base idle speed will usually eliminate the sound.

I only had this noise with a stock tune. Once mod'ed even a little, the engine needs less idle screw bypass air to maintain the idle.


For example, installing NGK BP8ES (or BP7ES), non-resistor plugs, gapped to 1.0mm, make the idle very smooth, and the base idle needs to be adjusted down.

 

The NKG site shows these plugs for the 85 928

Standard BPR6ES 7131 .028
V-Power BPR6EY 6427 .028
G-Power BPR6EGP 7084 .028
Iridium IX BPR6EIX 6637 .028

what is the difference between these and the BP8ES/BP7ES ?

 

No 'R'.

Colder. (NGK scale is opposite of Bosch.)

 

Sorry I just can't resist.

You wont find the whistle unless you hold your lips just right