I found this broken hose tracing a boost leak. Do I have 1 problem or 2?
 

Hello All,
I am trying to help my Dad find a boost leak in his 1982 Euro 930. It has a 1 bar boost spring, ghl exhaust(I think) and a K27 HF. So far I have tested the waste gate to confirm the diaphragm is holding and it passed with flying colors. Fluttered at 15lbs from the compressor and had no problem creating a vacuum on the topside of the diaphragm. I then took the intercooler off and cleaned up all the seals and reinstalled with care. I thought I had convinced myself full boost was back and the temporary cheap boost guage I had teed off of the vacuum line attached to the bottom of the wastegate was just not accurate. I thought maybe the 18' of vacuum hose I purchased at autozone and the $25 boost guage combined to a low although steady reading of 13-14lbs while drive at WOT(my dad is opposed to installing a quality gauge as he likes the stock dash). Although the car still sounds a little sputtery I think I sealed something up a little more with the reinstall of the intercooler as the boost guage was not holding as steady a reading and it seems to pull a little harder now(also a little coler out).

I was going to reinstall the stock spring and see what boost readings I get but then I noticed this broken hose behind the waste gate. I guess this runs to the bypass valve? So my first thought is it might have some effect on what I think is still a boost leak causing a sputtering kind of sound when boost gets up over around 7 lbs. Do I have 2 problems or 1?

FYI turbo blew its seals a bit early and let oil past a while ago. Rebuilt and oil from the exhaust went away. Not sure if the turbo seals were beat up after this hose broke as the bypass/recirculation process might have been effected and the turbo aloud to stall?

Thank you all for your input. You Porsche guys are the best. I run my M3 at your track days instead of BMW's. Much more of a community than the BMW croud. I thought about buying my dads 930 from him so I don't have to have the other German car at the track. Side rant. Thanks guys!

http://forums.pelicanparts.com/uploa...1350398783.jpg

You're looking at a very corroded emission system air pump to air injection manifold check valve for the left side cylinder set.
It's there so exhaust backpressure in the exhaust ports can't flow backwards into the left side air pump diveter valve.
There is or was another one on the right side and they probably have some other specific name but thats what it is.

It has nothing to do with intake manifold vacuum or boost pressure and has no connection to the intake system so there's no vacuum leak there. Most people put a generic auto part store cheap rubber hose cap and hose clamp over it when disabling the air pump emission system and leaving the air injection manifold/tuging on the bottom of the motor.

Best thing is remove the whole thing to get it and the heavy air pump system out of the way if it's still there and you don't need it and put plugs in the M10x1mm thread pitch air injection holes in the cylinder heads.
They sell those here on pelican.
Pelican Parts - Automotive Parts and Accessories - Porsche & BMW

Ok 1 problem and 1 project. Much better than 2 problems but not as cool as 1 problem would have been. Thank you so much! I had pretty much worn out the search button. I'm happy to hear the parts I was looking at in the engine bay are somewhat strange. I couldn't figure out what the I now know to be a fan in the back of the engine did. Looked like maybe a weird alternator with vacuum lines. I was seriously second guessing my understanding of a turbo charged car. I will remove all the extra emissions junk over the winter.

Ok so I guess I will rig up 15lbs to the whole system and listen for a hiss. Or maybe the starter fluid while idling trick. The duct tape method seems very tedious to get a seal on all the possible leak locations. Anyone have a favorite method?

Also anyone know if 18' of vacuum hose before the boost guage would cause any line loss?