when i have my A/C on and Max A/C on it will blow hot air occasionally for about 3-5 seconds 1-2 times a minute. i have no idea what could be causing this, which is why i came here. Anybody know whats going on???

 

I have the same problem with my 2001 f-150. I took it to the stealership and they said they didn't know what was wrong with it.

 

May help, may not.

On the Taurus SHO, this is a common symptom that occurs as the compressor clutch wears over time. On that car, the solution is to pull the clutch plate, remove a shim, and reasemble it with a smaller clutch gap.

Steve

 

are we actually talking hot air (like when you turn the **** to hot)? or same temp as it is outside air? could be an electical problem or plenum problem if you get hot air. if its the same temp as outside air it would be more of an a/c problem.

 

It could also be that it is happening when you take off from a stop. once you hit a certain RPM the a/c clutch/compressor will dissengage to give the engine more power.

Also, these trucks are famous for the blend control *** failing. (Potentiometer)

 

well it has happened the most over this summer, so we average around 85-95 degrees the whole summer. that being said, i dont know if its heater air, or air temp. from outside. all i know is that its pretty warm.

 

The compressor clutch disengages when you accelarate to allow for faster acceleration.
It also disengages periodically when the system is low in freon in order to protect the compressor.

 

This happened to me a lot when I towed across country. F-150 w/ 4.6L 4x4, towing a 2900lb trailer and ~800 lb. in the bed.

My mechanic said that when the engine is required to work hard, the AC is disengaged for whatever length of time necessary to reduce the load. Made a lot of sense, as my symptoms were only occuring on inclines and hills.

 

OK, this might not be the answer to your problem but it is something to check out. I have a e-350 van and the motor that opens and closes the heater door broke.
When the air handler door is in the up position it sends air through the hearer core and into your cab. when the door is in the full down positiion the air handler sends air through the A/C core and sends cool air into your cab.
It could be that the motor that controls the air handler door is getting stuck in mid position, then you will get half A/C and half heat.
locate the heater air handler flap motor and have some one move the tempeture control to hot then cold and see if the motor is turning ok.
On my van the shaft that controls the air handler flap cracked where the motor hooks to it and the motor never opened the flap all the way. I had to remove the heater core cover under the dash and replace the air handler assembly(ford won't sell just the door) it cost $160.00 .
I don't know if the heater in pick ups are built the same as a van, but it's worth a look.

Good luck!

 

AUeagle009,

I agree with syncmaster. It sounds like a blend door problem. Check out the blend door and the stuff that controls it.

Good Luck,
Bill

 

What kind of vehicle are we talking about here, how many miles? Different vehicles with the same symptoms could have different problems. The more info on the symptoms, the better able we are to diag the problem.

 

2001 f-150 4.2 v6 70,000 miles. may i add that i hardly ever use my a/c, but when i do use it it blows hot air occasionally.

 

Have you checked the system pressures? Look for signs of leakage at the front of the compressor, and at all of the connections.