5301113

iTrader: (18)

I have a hissing sound that i cant figure what is doing it.It's some where behide the TP or before the intake maybe one of those rubber pipes. The sound is always there. It just started last nite.Help me

AFASTYZFR1

iTrader: (55)

sounds like a vacuum leak

5301113

iTrader: (18)

I'm thinking the same thing but i cant find it

AFASTYZFR1

iTrader: (55)

I would tighten the intake some in the proper order which can be found on ls1howto.com, just to be sure....then look for and lines that are disconnected

hevymetalg

iTrader: (1)

is it like a whining sound cause my just started doing that too!

5301113

iTrader: (18)

no its hissing. It sounds like when air is coming out of a tire

5301113

iTrader: (18)

Nothing looks disconnected

hevymetalg

iTrader: (1)

get some carb cleaner and spray it around the manifold see if the engine dies out and that will be where you leak is

5301113

iTrader: (18)

OK after reading some posts.I hoping it's a ring seal or pcv rubber hose,egr ring seal.I'm hope it's not an intake leak

tording99Z28

iTrader: (3)

Are you throwing any Check engine lights? Check on the underside of the PCV hose where it connects to the intake. Mine opened up a crack right there from the heat and the angle of that rubber hose. Mine was also throwing lean condition codes for bank 1 and bank 2.

5301113

iTrader: (18)

No codes yet but i do need to check the PCV hose

5301113

iTrader: (18)

FOUND A CRACK ON THE PCV HOSE .I dont know what size it is to replace it
It the hose from the tp to the pcv , two inches long

AFASTYZFR1

iTrader: (55)

i think it is 3/8"

5301113

iTrader: (18)

thanks i will order it from gm

tording99Z28

iTrader: (3)

I just went and got myself a piece of 3/8" vacuum hose and used some clamps and made my own 2" piece that goes there. I tried to order just that little piece but its part of the hole PCV tube assembly which is like $110 from the dealer. If you find just that little piece for sale somewhere let me know please.

5301113

iTrader: (18)

Ok let me check in to it

ae13291

iTrader: (8)

i would also recommend changing the egr pipe seal! i dont think mine was leaking but when i took it out it looked all melted and screwed up! and its only like 5 bucks from GM

5301113

iTrader: (18)

Is that the little two inches hose before the PCV? It connects to the intake.

Chadlee2KZ

iTrader: (9)

Just did mine yesterday. SES light went off within 25 miles. Sounded cool while it was doing it like a baby turbo...

ae13291

iTrader: (8)

nope its the hose on top of the intake right after the throttle body! unless u removed ur factory egr system!