ha ha you guys like that title??? Ok here is the deal. My a/c will work when it is kinda cool outside, like at night. But when it is in the dead heat of the day, it gets weaker and weaker, and then quits. If I get out and pull the PCM fuse it will work for a while and then quit again. The other night we found a fan relay was out, and replaced it, and the ac started working again. Until today. The freon levels are fine. The clutch is engaging so I dont think its that. How does that pressure sensor affect things. What does that cause the system to do if it goes bad. Any other suggestions would be great.

 

As far as I know, the pressure switch just turns on the fan. if the fan doesn't come on, then you may have popped a reliefe valve which is on the back of the compressor. You may need to check you levels again. If the pressures are equal, and never changing, then I would think that meant your expansion vavle isn't doing it's job. it should have a temp bulp that runs down to the evaporator(the part that is inside the car) which tells it when to expand and when to close. that's pretty much what tells your AC to cool, or not to cool.

 

If it is blowing hot air and the freon and pressure levels are fine then it is most likely the compressor, that is what is wrong with mine too.