PCV How noisy should it be?

[tripletdaddy]

On my 95, 3.8 engine, I noticed when I raised the rpm while under the hood, the PCV become louder than I've heard before. It would take it awhile to quiet down after the rpm returned to idle even after a few to several minutes. Since this is the first time I've ever heard it do this on three of these engines I routinely have my head under the hood and am mindful of all new and existing noises, I don't think of this as normal. I've heard some PCVs sound like they are rattling on other engines, but this one has more of a hissing/buzzing/rattling sound. It almost sounded like a vacuum leak but didn't have a pure hissing sound to it. Is this normal on your Taurii? Does this sound alright?

[shorod]

Are you certain it's the PCV? What's it do if you increase the engine speed? How much oil are you getting into the intake? Sounds like you may want to check your compression on all 6 cylinders and see if you've got one or two that are pretty low relative to the others. I can't say that I've ever heard a PCV rattle or hiss. At least I've never attributed a rattle or hiss to the PCV.

-Rod

[tripletdaddy]

Originally Posted by shorod

Are you certain it's the PCV? What's it do if you increase the engine speed? How much oil are you getting into the intake? Sounds like you may want to check your compression on all 6 cylinders and see if you've got one or two that are pretty low relative to the others. I can't say that I've ever heard a PCV rattle or hiss. At least I've never attributed a rattle or hiss to the PCV.

-Rod

Yup. Took a listening hose to it, but I need to differentiate between the valve vs. the two rubber connections. They may actually be allowing a vacuum leak. If it isn't making any noise yet, higher rpm initiates the sound and higher rpm makes it noisier, lower rpm is quieter. I noticed with an extended high rpm, it was more noisy longer, so its return to less noisy at idle was delayed for a couple of seconds. I assumed that had to do with either the manifod vac having a similar delay in vac change or the extra generation of crankcase/blow-by gases that create higher pressure? It's too bloody hot here to test further. We have heat indices up to 110 F. That perfect shop with heat and ac probably isn't going to be coming for a long time.

I may just replace the valve and the rubber connecting hose and inspect the grommet. Has anyone found the aftermarkets to work all right? I've heard some have found only the Ford valve to be the right size and maybe even work better.