DIY_EFI Digest V2 #324

[George M. Dailey]

I'll check it but I'm fairly certain that my dual PCV valve setup is NOT OEM
design. Several people have told me that 13" of crankcase vacuum is not normal.

Thanks for the help man, I just might recover enough sanity to at least
appear normal to the untrained eye.

GMD

At 11:59 PM 9/17/97 -0500, you wrote:

>> I've got a weird one here. Every one I've asked so far has been stomped. I
>> drove my '89 5.7L TPI '58 chevy truck to Atlanta last weekend, 100mph
>> plus...420 miles one way from my home...so I'm perty sure it's not a
>> mechanical engine noise. The following is what I know. I think it's the EGR
>> valve or diaphragm resonating.
>
>whoa.. they had EFI in 1957?
>
>> When the engine is hot (just after getting off the highway) I get this high
>> pitch squeaking sound. Sounds like a belt but much louder. I can hear it 100
>> yards off.  Changed the belt, operated the engine with the belt off, added
>> many cans of belt dressing, and the engine still squeaks. 
>
>have you checked the power brake servo, if you have one? Vacuum causes a
>loud high-pitched squeak in those bastards if they have a hole. A girl i
>knew told me that her mechanic had informed her that "she had a pinhole in
>her diaphragm" and then told the rest of the story. Basically, a
>high-pitched very annoying whistle was present whenever her foot was not
>on the brake pedal. it's worth a look, let me know if i was right.
George M. Dailey
gmd at tecinfo.com