Help! What is this tube/hose?

[Dramlin]

Hello everyone,

While trying to diagnose a broken turbo boost gauge on my 2002 WRX I noticed that one of the hoses/tubes past the stock airbox was completely severed. I tried a bunch of google searches to figure out what the hose is, but couldn't find any information whatsoever. The below dirty pictures are showing everything just past the MAF. Does anyone know what this hose/tube is & what its purpose is?

[pzr2874]

Trace it back, it's either a BCS hose or recirc.

[zoe60]

I've only had my car about a month and it's my first turbo so I'm pretty ignorant about what everything is, but it goes back and to the left. It hooks to the bottom solenoid,sensor, whatever under the plastic cover by the strut tower. Could be boost control solenoid, but it only has two hoses. I thought they had three. Hope that helps.

[jts749]

It hooks to the bottom solenoid,sensor, whatever under the plastic cover by the strut tower. Could be boost control solenoid, but it only has two hoses. I thought they had three. Hope that helps.

That is indeed the boost control solenoid.

[zoe60]

Thanks. I need all the help I can get learning this car.

[Dramlin]

It does indeed route to the BCS. In working with a few dealerships to get a replacement hose there is no technical name for it.. Apparently people just generally refer to it as a "Boost Control Solenoid Vacuum Hose".

Thanks everyone for your help in figuring this one out.

[Dramlin]

For anyone that has this issue in the future, the hose is a generic 3.5mm vacuum hose that you can get at any auto part store for about $5. I actually used a 4mm without any issue, and I'm guessing you could even go as large as 5mm.