I have a 99 taurus with the duratec engine and I'm having a/c problems. The clutch and compressor are spinning and the low side pressure rises and falls accordingly. The charge of refrigerant in the system seems to be correct according to the gauge I have. The a/c lines do not get cold and the air coming out the vent in the cabin is about 5 degrees below ambient (I had read that it should be about 40 degrees below ambient in 80 degree weather). I don't have a manifold at this time to check the high side pressure. Any suggestions?

 

There is a blend door actuator under the center of the dash under the bottom. Make sure it is working properly when the temperature selector is changed.

 

I checked the blend door actuator and it appears by the recessed square indent that it is turning just shy of 90 degrees with the appropriate temperature changes at the vents ( is this the appropriate amount of rotation?). What looks like the evaporator core cover did have some condensation and a cool feel to it, but nothing that I would consider 40 degrees below ambient. The fans at the front of the car appear to be operating normally. Is it possible to turn the blend door manually with a screwdriver without doing more harm than good? I don't have the correct bit at this point to fit the indent. The temp of the evaporator cover does make me think it is something upstream of the evaporator, would you agree? Thank you very much for your help!

 

It appears that I was wrong about the system having the proper amount of refrigerant in it. I found some information that suggested that the compressor was cycling too often and that it was typically caused by a low level of refrigerant. I added a new can and it seems to be working properly, I'll continue to monitor the system for leaks. Thank you very much for your excellent advice. In the future I'll know how to check the blend door for problems. It had been a while since I had been on here and I was very glad to see you were still on!

 

Happy to see you are still using the forum. Keep in touch. The best way to test the blend door is to remove the actuator and move the door lever by hand. If you use a tool in the actuator, you can damage the little plastic gears inside. Good luck.