Had it converted at the dealer 10 yrs ago to R-134. Not blowing very cold. Does it just need a charge? What are high low side pressures supposed to be? Thanks

 

 

The parts store will probably loan you the set of gauges same as they would loan a ball joint tool.

 

If you did the proper conversion process wherein you replace the compressor, accumulator/dryer, and orifice tube; put about 3 oz of medium-viscosity PAG oil in the new dryer and the same in the suction port of the new compressor; flushed all the metal parts out with a clean NON-RESIDUE solvent such as lacquer thinner MEK denatured alcohol or even [gasp] A/C flush [/gasp] but NOT mineral spirits, paint thinner, brake cleaner, turpentine, parts cleaner, or other such imperfect substitute; replaced all the rubber hose sections with good new "barrier" hose (the kind that has the polyethylene lining) with 2 of the REAL A/C hose clamps on each hose end, as opposed to the little lightweight weeeeeeenie ones hanging on the card in the "radiator" aisle at AZ; made ABSOLUTELY POSITIVELY CERTAIN that the main rad fan is working to 100% or more of its OE efficiency; and it's not cycling now except when under minimal heat-transfer load (at night when it's only 70° out or the like); then I'd have to guess you musta used a GM white orifice tube.

It's all in the details and attention to utter perfection. A/C is a bit like automatic transmissions that way: it rewards people who are meticulous, thorough, and willing to cover EVERY detail, and punishes people who take ANY kind of shortcut or leave ANY detail to chance.