i dont mean to hijack your thread but i used this one to diagnose my own ac system that worked last summer but come spring it wasn't working, i jumped the low preasure sensor ac compressor kicked on so i bought some r134a and charged it to 45 psi now the ac works but it doen't seem as cold as it should be. if i bump the idle up to 1000-1500 the preasure drops down lower, my question is what psi should our systems be charged to?