A/C problems

I have a1999 Grand Prix GT without dual climate zone control. The A/C compressor clutch would not engage. I added 1 can of refrigerent and now the clutch does engage. The gage on the refrigerent can reads about 30 psi, the low range of the "good" area.
The A/C blows fairly cold out of the far right vent and the right vent of the center cluster of three. The far left vent (drivers side) and the left and center vent in the center cluster still do not blow cool .
What gives?

Normally that indicates insufficient refrigerant charge. Put some more R134a in small 4 ounce increments. How much to put in is based on the actual ambient temperature. Mine reads around 45 psi.

Thanks for the reply,

I actually put another can in yesterday before your post. The pressure still is only around 30 psi. The ambient temp was about 70 here yesterday, and will only be in the mid 50's today. Still have the same results, cold on the passenger side vents, warm on the driver side vents.

Do you think it is wise to attempt a third can? The A/C had been suffering poor performance late last summer into the fall. Obviously not used over the winter. Do you think the system is so low that it could require three cans to recharge?
Thanks for your input

Thanks for the reply,

I actually put another can in yesterday before your post. The pressure still is only around 30 psi. The ambient temp was about 70 here yesterday, and will only be in the mid 50's today. Still have the same results, cold on the passenger side vents, warm on the driver side vents.

Do you think it is wise to attempt a third can? The A/C had been suffering poor performance late last summer into the fall. Obviously not used over the winter. Do you think the system is so low that it could require three cans to recharge?
Thanks for your input

No problem and you are welcome.

Probably not and its not good to overcharge. You may need a decent set of AC gauges and determine where a problem may be such as a leak or major component going South. You'll need to check the high and low pressure readings to determine a course of action.

Have you checked/feeled the incoming lines to the evaporator? They should be fairly equally cold. Also check the in/out lines to the accumulator.

Hopefully there are no bad parts such as compressor, accumulator, condensor, or check valves, etc. Sometimes its good to get the system evacuated and then recharged.