I come up with two possibilities; One is 117 997 09 82 hose to vacuum control valve order by the meter
Second is 000 158 99 35 from turbochargedr to pressure convertor also order by the meter
I also only see this on the Garrett turbo and suggest you check their local distributor. It looks to just clamp on and be a simple rubber pressure/vacuum hose.
HTH, Jeff Zedic Toronto 87 300TD
