other day check engine light came on. code said running lean. figure its fuel pump or filter. but then started hearing a hissing noise while inside car. gauge shows 0 vaccum at idol and never drops bellow that. and went from boosting 22-24psi to 8-9psi. any ideas, advice anything?

 

SERIOUS vaccum leak. Check every connection that air runs through under the hood. All vacuum lines and intake/charge pipes.

 

he is correct above

 

vac/boost leak

 

just went to the store and on the way i got normal vaccum but still no boost and stopped hissing. but then started messing up again. help narrow down location?

 

I agree with boost leak, you might have popped off an intercooler pipe.

 

Start with the intake pipe and work your way to all the couplers to the turbo, LICP, IC, UICP, throttle body, etc.

 

ok to drive 5 miles a day till weekend? or is that just asking for more trouble

 

Just take 10 minutes and check out all your hoses, lines, anything that can cause a vacuum leak. I'll bet ya find it.

 

maybe check the pcv valve hose, egr valve vacuum lines, vacuum lines under the intake manifold that run too the egr soleniod. check all vacuum lines on itake manifold. while your at it, you might as well get small zipties and start tying all of them down.

 

I had the PO171 (system too lean) a few weeks ago, I cleaned my MAF with brake-kleen and it fixed it. Sounds like you have more issues than that though. Def check all your hoses and couplers.

You didn't blow a pipe off though, you can't drive the car like that, it just bucks and coughs.

 

What happens when you hit 8-9 PSI? Does it buck? Does it just fall on it's face? Does it back fire? If you can hear hissing it should be easy to spot. Also if you're running a vacuum line in the cabin to your gauge or a solenoid for your gauge check that spot. It rarely blows off there before a coupler but it's happened to me once on my AEM boost gauge solenoid, it's annoying.

 

What it sounds like is the head is heating up and expanding. Thus closing the gap between the head and intake manifold are closing. I would check the intake manifold gasket.