Boost at coldpipe, none at manifold, help?

[chickentendah]

My car has the following symptoms: exhaust backfires occasionally, idles roughly, wants to die after revving and letting off gas pedal

I am currently running the stock SR setup with the piping, SMIC, and bypass valve. With a vaccum/boost gauge, I measured the following things:

1) The stock wastegate line reports 10 pounds max boost when revving (connects to the stock SR coldpipe that sits on top of radiator shroud)

2) The FPR vaccum line reports a fluctuating vaccum at idle and likes to sit at approximately 10 In Hg

3) The FPR vaccum line reports ZERO boost when revving

Hoses connected to upper 2 vaccum nipples @ throttle body have no leaks. Lower vaccum nipple is plugged. Also, I can smell fuel outside the car sometimes.

What's going on here? Where should I look next?:help

[Hijacker]

you've got a faulty injector i believe. a blown injector can sometimes cause the FPR line to read low and jumpy. Also, check your intake manifold gasket. When it blows out at an intake port, it can cause the same symptoms. Because you mentioned fuel, I'm gonna have to guess that it's a bad injector.

Take a stephoscope or a screwdriver (in case you can't get a hold of some sort of listening device) and put the tip to each injector and rest your ear on the handle. Find the one that makes no noice.

[chickentendah]

both possible problems sound expensive =(.....

thanks for the ideas, i will definintely look into this

as for you other guys, any other opinions?

[Hijacker]

heavy throttle has OEM replacement injectors. they're used, but for 30 bucks, it's worth it. also try sr20store.com and see what they can do for you. intake gasket shouldn't be too much. get one offa early 90's sentra SE-R. i believe they shared the same gasket with our engines. try everythingnissan.com and see what they price the gasket at. that site's generally pretty fair about the price.