Finally up to the fun part of cranking up the boost. Building an FCD (as per the power primer) and figuring out the easiest way to tune it. I have a digital boost gauge that is teed into the Map sensor (Gen 2, so should be just for fuel cut). I've got a decent syringe that I can hook up to the vac line, so that I can supply any pressure I want independent of the engine, and read this on my boost gauge. Seemed perfect.
 
Now I thought I could try this in the stock configuiration with the engine idling. Apply pressure above fuel cut, and it should kill the engine at idle. However nothing happened, even beyond 20psi. Will fuel cut happen at idle, and would it be enough to kill the engine? Or does it only trigger above a certain throttle or rpm?
I'd really prefer to keep it functioning, so how do I check it?

id be betting it wont work at idle.... what year is your car?
 
the idle settings for the early models are sort of a default setting ignoring a bunch of sensors and variables....often it means they'll idle regardless of what else is wrong

Yeah, ideally try doing the syringe trick while driving or at least increase revs and see if it does it if you cant drive it.  
 
Cheers