I have a 96 F-150 I-6 and the a/c is having some problems. The problem is basically that sometimes the a/c will work and sometimes it won't. I can have it turned on and hot air will blow at me for 10 miles and then all of a sudden it will start working for another few miles and then stop again. Does this point to a fairly specific problem? I thought it could be either the switch, the compressor, or the clutch? Any comments?? Compressors are fairly expensive to replace aren't they?? Thanks!

 

If the AC is on, is the fan blowing? If so, is the compressor clutch engaged/disengaged when switched on/off?

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2000 F-150 XL,RC,LB,5.4,4R70W,3.55LS,
4-wheel disc/ABS,Chestnut/Parchment,
Ford bedliner & gas/wheel/spare locks,
3" cold air box modification,Superchip,
Dynomax ultra-flow welded 3" cat-back.

 

I had the exact same problem with an older Mercury Lynx. It also would stop working while sitting at a stoplight. Turned out to be the AC clutch overheating and not engaging the compressor. Unfortunately, I was able to "diagnose" the problem only after the clutch went "Tango Uniform". Fortunately, on that design, I was able to remove and replace the clutch without breaking into the system.

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2000 F-150 XLT Sport, Silver 4-door Supercab StyleSide
Short Bed (Only way to fit in the garage)
17" Sport Wheels with BFG tires, 3.55 R, 4.6l V8, Auto (First one in 20 years)
In-Dash Single CD Player, 60/40 Split bench dark graphite

Mods So Far
K&N Filter, Gatorback Spray-In Bedliner, Llumar ProShield Window Tint
WMS Velocity Tube

Future Plans
Superchip, Upgraded Speakers/Stereo
FlowMaster Exhaust, Nerf Bars

 

I have a 97 f150 4.6. When I turn on my truck and turn on the a/c it don't blow cold air until the truck start the ride for few minutes.

 

Rodriquez says:
I have a 97 f150 4.6. When I turn on my truck and turn on the a/c it don't blow cold air until the truck start the ride for few minutes
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Amigo, make sure the ignition is back to the neutral postion after you start up. We have had several fords that sometimes don't return to the neutral spot. This keeps some accessory items and the the A.C. from working. In your case, if the A.C. comes on a few minutes down the road, it may be that the key has vibrated back to the neutral spot, allowing the A.C. to come on.
Just a thought.
Ken

 

It sounds like your A/C system is low on freon. Bypass the low pressure switch and see if the compressor engages and you start to get cool air.

Jim

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1997 F150 Lariot SuperCab, Red w/ Gold, 4.6L, Auto, Leather Captain Seats, Bug Deflector, Viper 500ESP Alarm, Tow Package, Pendaliner Bedliner, Cobra Trapshooter 3 Radar Detector, CARR Tubular Nerf Bars, Sliding Rear Window, 255/70R16

 

You need to figure out if the compressor is running when it's blowing hot air. If the compressor is running and the return line (low pressure side) from the evaporator is cold, then you probably have a vacuum or control problem causing the air control door to operate improperly (i.e., sending hot air from the heater core instead of cold air from the evaporator coil).

 

Dewy,

You probably have this one solved by now but I just had a similar problem on my '97 Mercury Villager. My problem was the low pressure switch was working erratic. This switch is located on the dryer (looks like a thermos with tubes) and has two wires to it. This switch needs to be closed for the compressor to work. You can jump the two wires and see if the compressor runs. I wouldn't run it for long. Because if it does work it means that you are low on refrigerant or the swuitch was bad. The Switch is there to protect your compressor so if it is low on refrigerant jumping it for too long would be a no no.

peace

Travicaster