Hi I have a 93 1.5L Civic; I recently had my AC converted from R12 à 134A (I changed my drier, vacuumed it, and put new oil and put new 134A in) and now my compressor keeps on turning on and off. Could someone please let me know whats going on?!?!?!?

 

Probably a little low on 134.

 

nah that's not it, compressors are supposed to cycle on and off, when their pressures get too high in the a/c system or the evaporator gets too cold (so you don't form one big block of ice on the evaporator).

It might just be normal, I drive a Jeep Cherokee at work and that compressor cycle's on and off very rapidly, but it's normal. Remember, R-134a buildsup higher pressures in the a/c system than R-12, that's why you're supposed to use no more than 80% the amount of R-12 as originially indicated to put in R-134a amount, and in that instance, I would check actually for overcharging if it's that much of a problem, you would also noticed a decrease in cooling efficiency. How do you check such a thing, sorry but professionals come into play here, as they have manifold gauges and such that compare high and low side pressures to what they are nomially supposed to be.