slick98ta

I've been fighting this Vacum leak problem for almost a year now since I put this "brand new" LS6 intake on.
Since day 1 I've been getting PO171 and Po174 lean codes.The intake has been off 5 or so times,re torqueing it and checking for leaks.Nothing worked,I put the stock ls1 intake on and all was fine.
So last night I took the ls6 intake off again,checked everything then torqued it back down.Still did it, got both those codes again.Took carb cleaner and just sprayed it right over the top of the intake towards the back,and not in any particular area.Boom it reved up.So I know its leaking.

So today I start the car up and put my hand in the back of the intake and hear and feel a small leak coming from that piece where the brake booster hose goes onto the intake.That orange O ring isn't seated right in there isn't even flush to the intake.I compared it with my stock ls1 intake and its flush or sunk in flush and you don't see the orange ring.

So on the ls6 intake I just try pushing the plastic fitting in to try and get it flush and no can do,it don't move.So I'm thinking of just RTV ing it in there so it don't leak.What do guys think?

I just can't believe I buy a brand new intake about a year ago and its more than likly been messed up from day 1.So you guys out there that might have the same type of problem that i've been going through,thinking you checked every vacum line on the car,try looking at that piece in the back.

Sorry its so long,thanks for any input you guys can give me
And here's the picture to compare the LS6 intake to the LS1 intake in the back,you can see what I'm talking about. : LS6 inatke vs. LS1 intake web page

Mark

Nice4thgenZ

iTrader: (10)

ttt

Tin Indian

If you havn't done it already, you [must] remove the two black plastic hold down clamps that attach to your knock sensor wires. They are attached to the wires with some very strong tape. If they are not removed, they will not allow the intake to fully seal with the heads. That new LS6 intake sits lower than your old one, so you need to remove the wire clamps.

You don't need any silicon sealant or anything extra to seal the manifold to the heads (just the factory seals that came with the manifold).

Ron,

Tin Indian

After reading your post again, it appears that you don't have a leak from the intake to head mating surfaces, but rather from where the MAP sensor pushes into the back of the manifold. Is that correct?

Your MAP sensor looks different from the one on my LS6 intake.

It should have a wire connector attached to it, 1 large diameter brake booster hose, and 1 small diameter hose that goes to the air cond. vent system

Tin Indian

Ok, I just looked at the pictures again....You are missing part of the MAP sensor. It fits in where you see that big open hole in the sensor.

Your pictures only show part of the MAP sensor.

The pic below has the wire connector part that goes in the hole (missing from your pic)

slick98ta

[quote]
Ok, I just looked at the pictures again....You are missing part of the MAP sensor. It fits in where you see that big open hole in the sensor.

Your pictures only show part of the MAP sensor.

The pic below has the wire connector part that goes in the hole (missing from your pic)

Yeah I know its missing,I pulled it out when I was taking pictures.Here's what I did now.I pulled that big circle thing out that had the orange O ring in it. Then RTV the hell out of it then pushed it back in.I hope it holds.I know that where its leaking now because I started the car and wiggled that piece back there and could get that hissing"leaking" to stop and wouldn't hear it anymore.So that when I pulled the intake back off and seen that its not even seated in there all the way.And probally never was,because this intake leak problem i've had has been there since day 1.

Btw: the plastic clips were already removed from the wires from the first day I put the intake on.

TheDogofWar

iTrader: (2)

Yeah thats certainly in there wrong. I wouldn't be comfortable with just RTVing it. When I first got my LS6 intake I saw that and couldn't help thinking WTF. Why did they make it a seperate piece like that? I don't know how it comes out but it has to some way. IMO you should get it fixed correctly. If it were to come loose during a WOT run, could be bad.

slick98ta

I took it out.The way it fits in there,it wouldn't get sucked through anyway.There's a lip all the way around the inside where that piece goes.Kinda like tring to fit a quarter through a nickel hole.