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68C15 · 08-19-2008, 08:05 AM

it sounds like you have a problem with the lower mode door or the actuator. it has a brown and a black hose. it is a dual action diaphram.
wait a minute, you said you catn switch from defrost to vent either? the vaccum flows from the manifold (drivers side) to the ball thing mounted to the hood. then to the dash. start tracing the hose under hood using the emissions sticker as a guide.

08-19-2008, 08:05 AM	#6
68C15 blood type; Retumbo Join Date: Jan 2004 Location: next to my reloading bench Posts: 10,269	Re: blower control problems it sounds like you have a problem with the lower mode door or the actuator. it has a brown and a black hose. it is a dual action diaphram. wait a minute, you said you catn switch from defrost to vent either? the vaccum flows from the manifold (drivers side) to the ball thing mounted to the hood. then to the dash. start tracing the hose under hood using the emissions sticker as a guide.