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Old 02-03-2012, 07:14 PM   #1
tucsonjwt
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Join Date: Jul 2007
Location: Tucson, AZ
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Vacuum lines and Cruise

I am replacing the power brake booster and thought I would replace all of the vacuum lines inside the truck. I see one big vacuum line going from the servo to the cut out switch at the brake pedal arm.
But all I see for the HVAC controls are very small diameter color coded lines going to the various vacuum actuators and then one small line at the end of the run into the passenger side vacuum tank on the engine side of the firewall. Is that tiny line the source of vacuum for all of the other HVAC to vacuum actuators? Does anybody know where I can get those small diameter vacuum lines, much less color coded lines? Those small lines have special connectors at the ends to attach to the actuators and it looks like they are fused to the vacuum line, so I don't know if those lines are even replaceable.
I think I have a vacuum leak because the cruise control cuts out when I turn on the A/C.
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Old 02-04-2012, 03:57 AM   #2
CJ_Chevy
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Location: Portville, New York
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Re: Vacuum lines and Cruise

i just went through and installed all of my interior vacuum lines as well. if i remember, you are correct. if you have factory cruise, then you will have the tube going to the switch for you brake pedal. And yes, that little black line is the source for all of the hvac actuators. as for replacing the small diameter hoses, i had to replace one of mine. I am into gas powered rc cars and the silicon fuel tubing for them fit real nice and sealed around the actuator ports. i didnt need to use the little rubber elbow lock thing. you can get small fittings for the tubing at most autoparts stores. you just might have to be careful in how the tubing ties into the control switch at the HVAC controller.

any hobby shop that has rc cars will have the fuel tubing, and it comes in various diameters, sizes, lengths, and even colors.

and you might want to check where the vacuum is coming from on the intake. there is a 3 way tee behind the carb... one for cruise, one to go to the vacuum canister for your hvac, and one to the transmission modulator (on automatics).
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