i have a 2001 ctd 2500 with ac well yesterday i went to runing the ac but it never got cool it was just like the outside temp so i went by autozone to get one of those do it yourself ac recharge well i check the coolent in the ac system with a gauge that comes with the kit but the gauge said the coolent was fine but then i noticed that the ac pump would come on then it would buld pressure then it would cut off then lose the pressure and do it all over again.so does anybody know anything about the ac on our kinds of trucks???

 

Is the AC compressor clutch engaging properly? Theres a connection at the evaporator where the pressure switch is. You can jumper across that to rule out a bad switch.
Theres also a relay in the engine compartment fuse box you can try.

 

Sometimes just tapping on the pressure switch with a wrench will make it work-- for little while. Then you will know whether it needs replacing.

 

I know quite a bit about the a/c systems on our trucks and the first thing you need to do is post some psi readings low and high. Get it looked at by a pro, or at least beg, borrow, buy a set of gauges and get us something to work with. My blindside guess is that you are going to need a compressor.

 

My pressure switch came back to life after I re-seated the connector. Looks like to get at it and replace it youd need to drain off the refrigerant =(

 

Anyone ever have luck rebuilding the sanden compressor? I have a torn valve in mine causing it to work a little some of the time. Looks like I can order the parts for $100 but that alot cheaper than $350 for a new one.

 

I have one available if your interested

 

After the first year on my 01 my ac started getting weak. I added a bit of freon or whatever it is these days and it came back. I have had to add it every summer now and it seems to last the summer. On mine it seems if I just fill it to the high side of the acceptable range it makes the difference. Every year when I add it it is still in the acceptable range but just on the low side so I fill it to the high side and then good ac. There obviously is a small leak or something but for the cost of a can of freon once a year not sure it is worth chasing for such a small leak.