vacuume leak?

[Pit Crew]

Hi guys, recently i have heard a hiss that sounds like a pressuer leak on the driver side rear of my motor, pull and plug the vacuume line and it stops. Dose anybody have another idea about what causes this?

[truckinL33]

Dry rot, or a cut in the line you took off? Too lose on whatever it is that it connects to?

[Pit Crew]

I took off the line this weekend and replaced all of the hose parts and it still leaks, the only other piece I could think of leaking was the gromet that is in the valve cover, got that and changed that too, still leaks I just dont get it where else dose this go? valve cover gasket maybee?

[txarkitekt]

Are you talking about the brake booster vacuum line? Or the PCV line that goes from the back driver's side valve cover to intake?

From the sound of it, you looked right past the problem. It sounds like the vacuum line going to the brake booster is your culprit.

[Pit Crew]

Are you talking about the brake booster vacuum line? Or the PCV line that goes from the back driver's side valve cover to intake?

From the sound of it, you looked right past the problem. It sounds like the vacuum line going to the brake booster is your culprit.

Its definitly the line into the valve cover, when I pull it out and cover the end the sound stops and my idle changes, thats why i changed all of the rubber parts and pressuer tested the hard plastic line, thats all good just not sure where to look next.

[truckinL33]

Did you check the other end of the line?

[Pit Crew]

Did you check the other end of the line?

I would guess you mean the side on the intake manifold, unless this is connected somewhere else I don't know about, but yes I cheched each piece of the line by themselves

[truckinL33]

Unfortunatly, it's hard to troubleshoot without seeing it. What year truck, and engine? I'll try to see what it could be by looking at my truck tonight.

[Pit Crew]

it's an 03 5.3, sorry forgot to mention that