rb20 intermit problem please help out

[91240sxrb20det1]

ok i have a 91 240 w/ rb20det. ive had the swap for like 3 years now. just recently the motor has been shutting off intermittently . ive noticed when i pulled up to a stop light the engine rpm were fluxin then as soon as i try to give it gas it would die immediate. does not always do at idle. its not speed related or necessarily rpm dependent. my boost/vacuum gauge reads fine at 20, and when its dies it just goes from 20 vac to 0 and engine dies of course. like i said before the swap is not new and just now has been a problem. its all stock except i have a fairly new walbro 255 pump and new fuel filter. any help on this would be great. thanks

[Sil240]

Check for boost leaks.Make sure you have mini zip ties on all you Vac lines

[zmannz]

Sticking bov? My stocker got damaged and it did this. I had a wandering idle and it would be idling fine and then it would just die usually. Occasionally I would let the motor idle down from near red-line and it would just idle down dead, occasionally you would hear it sort of pop loose and idle would regain normal sound.

[gawdzilla]

try a new MAF