As I posted elsewhere, I have the dreaded P0455. After the N80 valve, there is a "y" connector and two lines. One goes to the "t" fitting under the intake manifold, which is the LDP leak detection pump line.

My question is, what is the other line? It runs along the side of the air cleaner housing and down below the tube from air cleaner to turbo. My vacuum diagram names its one way valve "between evap canister and intake manifold before turbocharger" which must apply to the line itself.

In my case, it does not pull a vacuum and seems loose as I wiggle it. So it may be the cause of my P0455 problem.

I would like to have some feedback from you all before I put the front in service position to see where it goes, if there is a break, etc.

Thank you,

John

 

What do you mean when you say it doesn't pull a vacuum? What did you test and how did you do it?

The EVAP line has a tee so that there is always one source of vacuum. When the motor is boosting, vacuum is drawn from the TIP connection instead of the intake manifold.

Going into service position seems a bit excessive to address your problem, unless you need to do a bunch of other stuff.

 

No vacuum at idle at the ACF line to before the turbo. I removed the line at the "t" and felt for a vacuum and put a vacuum gauge on it.

Your explanation of a need for a vacuum source when in boost explains why there are two lines, very helpful.

Rather than service position, I may be able to take out the air cleaner box and the under-engine splash panel for access to see if there is a leak where the ACF line connects to the intake tube from air cleaner to turbo. It is buried.

Questions:

Does the ACF line only pull a vacuum when in boost? Will it not pull a vacuum at idle?

What is "tip line", that is what does T I P mean?

Thanks,

John

 

ACF line?

TIP is the turbo inlet pipe.

 

Thank you. As posted elsewhere, the P0455 was due to a 1/2 inch hole in the line from charcoal canister to the gas tank.

John