Why is this happening?

I had no action from my HVAC blower motor- so I took it out cleaned off 14 years of crap and put it back in. Now it works- but will only blow air out of the defrost vents- YES I know, vacuum leak!!!!

However, when I get up to about 45 mph it will kick on to whatever vent I have selected (AC, Hi-Low, Heat, Vent, etc). It will stay like this until I slow down or stop. What causes it to switch? Does the vacuum preasure appear at higher speeds? :huh:

Can anyone CONFIRM Napa having the CCV replacement parts??? I looked all over the website and can't find them- what are they under???

I even ran the part numbers from a previous post into the napa datbase and nothing!!! (I am retracting this).... When you search on the website do not type in the dash. The parts come up, but with not picture!


Thanks
PRL

Vent-I always figured it was the overpressure on the windshield at speed, that helped/pushed the distribution door inside the HVAC box to close, to the floor heat/ or proper position (same with the panel distribution door). Don´t know for sure, but always figured the default position for the defrost/floor heat door, was defrost. Just a guess.
Most times I´ve tested, the more open the TB (more throttle), the less the vacumn.
Unless I´m remembering wrong, the HVAC system, holds vacumn with the motor off, there is a check valve in the vacumn canister (may also be one in the line someplace). Disconnect the heater vacumn supply, at the firewall (passenger side), believe there is a flexible coupling, hooked to a black vacumn line (coming from the cannister). Most times I´ve disconnected there you can hear it suck.
Can disconnect the major vacumn supply to the canister at the manifold and give it the old suck test, you´ll notice if it´s loosing vacumn pretty quick. Use your tonge as a stopper. Not very scientific, but funtional. Can do the same to the HVAC side of the system after the canister.
There is a vacumn can/actuator for the floor/defrost door, on the left of my HVAC box (external), above the gas pedal. Mine leaks a bit, I can hear it relax and suck a little air when I turn the motor off.

Thanks for the help- that was very informative! I can't wait to go check all those!!!

By canister do you mean reservoir in the bumper?

I can't help you with your HVAC issue, but I can tell you that the CCV stuff is a dealer only item. I paid roughly $95 for all the lines for my old '88 XJ.

gw204 said:

I can't help you with your HVAC issue, but I can tell you that the CCV stuff is a dealer only item. I paid roughly $95 for all the lines for my old '88 XJ.

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I disagree (I think)- go to NAPAonline.com I was a disbeliever too!

NAPA PARTS:
715-1367 $18.99
715-1366 $18.99 (one is the air filter side, and the other is the valve cover side)
715-1365 $7.69 (This is the little vacuum tube that goes from the intake manifold to the rear of the valve cover. Includes Gromit)

They all come up, just type the number without the dash on the first screen.
They are listed as Belkamp products. Belkamp is a part of NAPA that repackages items made by other manufacturers into a NAPA box.

I can't wait to go to my local NAPA!!!

prljeep said:

Thanks for the help- that was very informative! I can't wait to go check all those!!!

By canister do you mean reservoir in the bumper?

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Yes the vacumn resivoir (or canister in the bumper). Have found the major vacumn feed,under the battery rotted and the feed from the resivoir to the HVAC or cruise control (don´t really know which) pinched and cut under the battery where it goes under/through the headlight/radiator clip.
Was also loosing a significant amount of vacumn, at the ERG vacumn transducer, that had some affect on how the heater controls functioned.