legacycentral bbs

I rerouted my mbc lines this past weekend while doing my i/c and I forgot to ziptie the compressor outlet line to my mbc. I started to notice that I was starting to get increasing boost while out for a drive yesterday. Now I was just out shortening my new DV setup hosing and i accidently snagged that line on the mbc and it came right undone. Here's my theory. As my engine bay got hot and the vacuum line got warm it expanded and starting leaking more and more, which kept the wastgate actuator from opening. This is why I was getting increasing boost throughout my drive.

I know that poeple have complained about weird boost issues and strange creep issues and maybe it's from loose, or loose once hot, vacuum lines on the turbo, mbc or wastegate actuator. Make sure you ziptie all your connections securely folks.

Woah. I'm glad you noticed before it caused damage!

Your theory sounds plausible. Definitely clamp all the hoses down somehow. Zipties should do fine, but make sure they're quality zipties and that they're UV resistant. Even spring-type clamps should work.

Also, make sure you're using the right size hose. The compressor outlet and wastegate actuator use 5.5mm hoses from the factory. 1/4" vacuum line usually fits snugly. Fuel line may be even better to use, though then a ziptie may not be able to clamp hard enough.

Yeah, I've always had them ziptied in the past and never had a problem before.

I wasn't worried about damage really, I turned the boost back down as soon as you and Phil left. I am running 10 psi and the highest it went during the drive was around 13-14 psi.

Anyways, I ziptied the line and now have a steady 10 psi with no issues.