On my '87 GTi there is a vacuum hose that starts at the bottom side of the short plastic boot attached to the throttle body and ends up connected to a nipple on the cylinder head. Does anyone know what this vacuum hose is for?
Also, on my car someone has carved a small (about 2 mm dia.) hole at the elbow of this hose. It most certainly is done deliberately as there is nothing even close to rubbing against that spot. I'll happily take suggestions on what the purpose of this hole might be.
That hose supplies air to the head for the air-shrouded fuel injectors that the CIS-E cars have. It's not strickly speaking a vacuum hose as it picks up air before the throttle plate. Part of the air the cylinders suck in comes in via that hose to the head and then through small ports in the injector inserts. The injectors don't fit directly into the head, but rather sit in plastic or brass inserts. The purpose of air-shrouded injectors is to help better atomize the mixture for increased power and lower emissions.
Todd Seattle,WA '86 GTI, Red of course. (exciting racey car) 256,000 miles '87 Golf, Polar Silver. (boring work car) 458,000 miles
Thanks for the info!
snipped-for-privacy@racertodd.com wrote:
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