Author Topic: cabin fan system question (1988 pickup)  (Read 641 times)

0 Members and 1 Guest are viewing this topic.


  • Offline Rock Crawl'n
  • **
  • Turtle Points: 418
  • Posts: 57
  • Member since Jun '16
  • Crawling with Marlin
    • View Profile
Re: cabin fan system question (1988 pickup)
« on: Jan 13, 2020, 03:42:30 AM »
To answer your first question, yes the intake is under the windshield cowl. Remove the wiper arms, then pop the hood to access three Phillips screws and two push pins that hold the cowl to the cab. There are big holes in the cab for air to flow in. Some trim levels have plastic screens that pop in to provide a rudimentary filter. If you're interested, I have a set. If your truck was originally equipped with A/C, the A/C evaporator in the dash is a big collector of debris since all HVAC air flows through that no matter what the temperature selection.

To access the controls you really need to remove the entire dash. Nothing is sealed, it can all be accessed and serviced, it's just a pain. I wouldn't be surprised if the heater valve under the hood is frozen or or stiff. This puts a large strain on the blue HVAC cable, which might have bent. Also, when stuff stiffens up, sometimes the HVAC control assembly simply cracks. So don't force the levers if they are stiff. A good teardown, clean, and lube can make all the HVAC move like butter and save precious parts from breaking.


Related Topics

33 Replies
Last post May 02, 2004, 07:31:54 AM
by brainlessfool
4 Replies
Last post Nov 10, 2006, 11:56:59 PM
by BigMike
5 Replies
Last post Jan 07, 2011, 09:39:10 PM
by yoshaleng
0 Replies
Last post Jul 11, 2012, 07:55:08 PM
by COToy91
5 Replies
Last post Sep 25, 2012, 10:46:29 PM
by 4-lo