[suspect]

Does anyone have a line diagram for the engine cold side where the air box and charge pipe is? I have an intermittent 30ff code boost not meeting target. It happens randomly and the target would be 16.5 but it will only hit 13.5psi. Other times it gets 16.5-16.7psi.

I replaced the ofhg and disconnected three vacuum lines (#5,#6 and another going around the air box which I think goes to brake booster?) and the rear diverter valve. This has likely caused the issue and a diagram would help before I think of fixing a pinched intake manifold gasket.

On realoem I could only find the hot side vacuum lines.

[suspect]

Does anyone know what is the tube/pipe going into the front intake? What does it do? It’s held by a grey twist locking mechanism.

[dmckmc]

Originally Posted by suspect

Does anyone know what is the tube/pipe going into the front intake? What does it do? It’s held by a grey twist locking mechanism.

sounds like you are describing the bypass valve (blow off valve) hose. it routes bypassed air back to the intake (instead of vented to atmosphere).

[suspect]

Originally Posted by dmckmc

sounds like you are describing the bypass valve (blow off valve) hose. it routes bypassed air back to the intake (instead of vented to atmosphere).

I think I left this unlocked. After turning it to the opposite position, the car has stopped throwing a 30ff shadow code. Don’t know why it works if all it does is route bypassed air back to intake.