1988 F150- Heater Problems
#1
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1988 F150- Heater Problems
I just replaced a bad heater core on my truck but it will still not blow hot. I checked the core and it is getting hot and I am blowing air but nothing hot.. any suggestions?
Alex
Alex
#2
Dailydriving300ci-of-fury
Welcome to the forums! If you've ruled out that the core is getting hot, and yoyr blowing air then there's one more thing. Make sure the vent is open to blow across the core itself. I'm not sure exactly how the interior vents operate but your cables might not be opening to the core, thus just recirculating truck temperature air.
#3
My '89 has A/C, all vents and doors are vacumm operated. I currently have the same issue. My truck sat for 19 years before I bought it, all the vacumm lines to the heat & AC are dry rotted. I started replacing the easy ones I can see and now have a little air moving into the cab, but not much.
#4
November 2011 TOTM Winner
There is a cable attached to the lever you adjust to set the desired temperature. It goes to a mixing valve which gets air that has passed through the heater core and mixes with the other source, either AC or outside. If this cable was broken or one end not attached then you would not be able to adjust the temperature of the air coming in the cab. I have an 88, the cable is notorious. It either breaks, disconnects or breaks the linkage it is attached to at one end or the other. It is easy to replace, simply pull the climate control head out of the dash, you'll see it right away. If your problem is not on that end, pull the glove box and follow the cable to its linkage.
#5
Dailydriving300ci-of-fury
Originally Posted by 5Rangers
There is a cable attached to the lever you adjust to set the desired temperature. It goes to a mixing valve which gets air that has passed through the heater core and mixes with the other source, either AC or outside. If this cable was broken or one end not attached then you would not be able to adjust the temperature of the air coming in the cab. I have an 88, the cable is notorious. It either breaks, disconnects or breaks the linkage it is attached to at one end or the other. It is easy to replace, simply pull the climate control head out of the dash, you'll see it right away. If your problem is not on that end, pull the glove box and follow the cable to its linkage.
#6
Senior Member
Check the white vacum line underneath the hood on the passenger side. It goes to a cylinder in the corner of the firewall and inner fender. Normally those will dry crack. Dig back into the harness where it comes out and cut it off. Get you some 5/32 vacum hose around 20" should do it slide one end onto the cylinder the other end onto what is left in the harness. That should do the trick.
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1988 F150- Heater Problems
There is a cable attached to the lever you adjust to set the desired temperature. It goes to a mixing valve which gets air that has passed through the heater core and mixes with the other source, either AC or outside. If this cable was broken or one end not attached then you would not be able to adjust the temperature of the air coming in the cab. I have an 88, the cable is notorious. It either breaks, disconnects or breaks the linkage it is attached to at one end or the other. It is easy to replace, simply pull the climate control head out of the dash, you'll see it right away. If your problem is not on that end, pull the glove box and follow the cable to its linkage.
Alex
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Check the white vacum line underneath the hood on the passenger side. It goes to a cylinder in the corner of the firewall and inner fender. Normally those will dry crack. Dig back into the harness where it comes out and cut it off. Get you some 5/32 vacum hose around 20" should do it slide one end onto the cylinder the other end onto what is left in the harness. That should do the trick.