a/c charge

[94conv.]

I was running the a/c last night and it didnt seem to be cooling very well so i put in a can of a/c tune up that had the oil and 134a
(1994 has the 134a) so I put it in and now the high side is really hot and the cold side feels about right but while idling I didnt notice the compressor cycling? it was a 5oz can, is it possible to have an overcharge? I dont have the guages, I was going by feeling the low side and feeling the air temp inside the car. It blows cold when on straight air now, just worried about the compressor

 

[Robertwav1]

You really need gauges to tell the proper charge. Head pressure at an idle will always be high. I usually charge a vehicle while keeping the RPM's at about 1500. On the vette, about a 1000 RPM. The compressor should always be engaged when on. Low suction will cause the compressor to cycle which could mean short gas. Look at the suction line....you shouldn't see any freezing at all, if you do your undercharged. Be extra carefull with air, if you get any in the system, head will be high even when driving.