Originally Posted by Merlin 91/97
What'* the purpose of the boost bypass trick?
I was wondering the same thing, and I _am_ a Gearhead...
I'm going to have to do some light bedtime reading in the service manual and see what this thing'* all about.
As for the foam over the open port, yes, that'* recommended for anything that may draw vacuum, as an air filter. My old K wagon had a simple rectangle of foam stuck over a vacuum port for the MAP sensor or something connected to it, I forget now... looked a little crude, but that'* how the factory did it.
Keep in mind that if you're controlling a vacuum-operated device, you can't switch "off" a vacuum; you have to allow air in to collapse it. So anytime you need to open up the system to outside air like that, you should have some sort of filter on it. Also, depending on where the open port is located, you may need to worry more about whether the vacuum is going to snork up _rainwater_ through that port, not just dust, so again, the foam was used to keep road spray out of the vacuum control systems in areas where that could be a problem.