I just bought my first diesel and when I was installing my 100 plate I noticed the previous owner had the hose blocked off in the pic. My questions are what is blocked off and why would the PO block it off? Thanks

 

That is a boost line which is supposed to go from the back of the AFC housing to the wastegate actuator on the turbo. In that for the wastegate on the turbo is nonfunctional, was probably done for more boost. If you are making much over 35psi it would be good to hook it back up then use a boost elbow to set your desired boost.

 

looks like the line coming from the wastegate to me.

if it is he blocked it so the WG won't open but he blocked the wrong end boost enters that tube not exits.... i think, but hey i've been wrong befor

 

The diaphragm in the wg actuator is probably ruptured, which would bleed off Boost from the AFC, resulting in the engine running as naturally aspirated, with not much power.

In the pic, just below the blocked rubber hose, you'll notice the "tee" outta the rear of the AFC housing - that black nylon tube goes forward to an elbow on the side of the intake, taps off manifold pressure.

A plug occupies the hole in the "tee" where the fitting for the rubber tube connected.

Allows the engine to develop max Boost, uncontrolled.

If ruptured, a new wastegate actuator will be required to correct the situation.

 

The way he has got it blocked is the right way. Personnaly I would leave it unhooked and forget about it.

 

The wrong end of the hose is blocked off but it looks like a plug was screwed into the tee where the hose was supposed to go.
Leave it alone.

 

not a big deal! the blocked off hose, keeps dust from entering the WG line.
what blocks it, is the plug under there!(pic)

i personaly never block em anymore, We've blown 2 turbos already!

 

I block them up to 35psi

 

Thanks guys, I just wanted to find out what it was, now that I know I'm gonna leave it blocked off. Thanks again.

 

and this is the most important part if you unhook it here. It doesn't really matter which end you block off if you unhook it at the afc and plug it off.