no matter which position i have the dial for my vents on it blows out the defroster. i read up on it and apparently this happens when you have a vacuum leak. i checked the vacuum resevoir and it seems fine and so far i couldnt find any damaged hoses. my question is if i have done the hub mod on my 98 can the vacuum be leaking at the hubs?

 

Your blend door could be broken.... not sure if the rangers have vacuume acuated motors or not.. but if the door is broken prepare to rip your dash out...

First pull the **** controls out of the dash and check the back to make sure everything moves how its suppose to..


PS- 30% of the time, something falls down in the defrost vents.. and jams the blend door.. so even if its working something could be blocking it..

 

The HVAC controls and the PVH system use the same vac source and reservoir. A leak at one affects the other.

Be sure to look at the vacuum line that runs back to the HVAC system. It can get disconnected during engine servicing or melted by the exhaust manifold if misrouted.

Also check the connections at the reservoir and the condition of the reservoir itself. I believe that it is between the fender and inner fender on a 98.

 

i was looking up the blend door and it looks like only trucks with ac are affected and i dont have ac. do i still have a blend door?

 

Yes you do. The term 'blend door' usually refers to the door that controls the hot/cold mix via the temp dial on the HVAC panel. It is often positioned by an electric motor but some Rangers had a cable arrangement instead. The door can be fully open, fully closed or any place in between depending on the dial position.

There are 3 other doors that are controlled by vacuum servos and are either open or shut in normal operation. These control the airflow path through the system selecting a combination of fresh/recirculate, floor/panel and panel/defrost. When vacuum is insufficient to operate the system, the default path is through the defroster registers.

 

i dont have a problem with the always being either hot or cold so im thinking that the problem has to do with the other 3 doors

 

I had the same problem and it ended up being the rubber hose that the vac line slides into on the reservoir behind the pass. side fender. I just pulled out the vac line and the rubber hose, then replaced the rubber hose. Another connection was near the reservoir or under the air box (dont remember) that had the same rubber hose and it leaked also. The rubber hoses used for the connections didnt look bad but they had very very small cracks in them that I couldnt see until I took them off.

I had the exact same problem as you and also converted to manual hubs, but I did cap the vac lines going to the hubs after I did....

 

check the vac lines

 

theres nothing wrong with the ***** becuase everything works fine for the first minute or so after starting and all of the vacuum lines that i can see look to be in very good condition. the only other thing that i can think of is that the leak is in the hubs. what is the best way to cap these lines?

 

I went to autozone and got a "kit" I guess you would call it with a couple different size vacuum line caps. You should be able to find them at most autoparts stores.


Mine came with caps like the smaller ones here.

http://www.autozone.com/R,NONAPP5308...ductDetail.htm