Throttle body question

Joined
4 February 2006
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66
I just installed a new intake system. There is what looks like a vacuum hose coming from a circular diaphram on the throttle body near the coolant reservoir tank. The new outlet tube is made of carbon fiber and did not have anything to connect the hoses. Does anyone know what could happen to engine ?performance if the hoses are not connected? The engine seems to idle fine. What is the purpose of this hose? There is also a bigger hose coming from the engine.
 
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The large hose is probably the positive crankcase ventilation (PCV) hose. This needs to be hooked up to the intake otherwise it will just vent into the engine compartment and emit oil vapor, making a mess over time. The other hose needs to be connected also, it's probably a dashpot. It acts as a shock absorber when you let off the gas pedal real quick. It brings the throttle slowly to idle for the last little bit of travel. The engineers that designed these cars didn't put anything on them that they didn't need. Obviously vaccumn is needed to operate whatever is at the end of the hose, I don't have the manual open in front of me. It's at home in Boise, I am in Afganistan. (isn't the internet a wonderful thing) By the same token if they put it on, I would try to connect it close to where it was on the original intake. You may have to drill a hole and install a small steel tube with some epoxy to get the hoses connected. You may want to get a small gromet and drill a hole to fit it. Some aftermarket stuff is so general that it doesn't have all of the necessary connections for all of the original hoses.
 
Thanks for the info OldMNSX. My old intake had a rubber piece connecting the t/b with the air box. This new one is carbon fiber. I like your idea of epoxing a metal sleeve to fit the hoses. Has anyone else experienced this same situation? Thank you in advance.
 
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