Recently my a/c doesn't seem to be as cold as before. I dropped by the local a/c shop and they saw one of the big rubber a/c hoses (the one passing over the air intake) having oily residue on it. So they say there might be a leak.

I was in a hurry and needed to use the car so I just ask them to top it off. They did. However, only the rear a/c blew cold. The fronts were not blowing as cold.

The shop tells me it could be an expansion valve problem. They prescribed, replacing the leaky hose, a new drier, a/c cleaning, and 2 new x-valves. The total bill rounds up to around Php5k (includes labor and materials) but will take a whole day to do so I just set an appointment.

This evening, I was using the rig and the front a/c seems to blow cold again. It only loses efficiency in hot weather, maybe? Or did the R134 top off work?

Do you think the shop's diagnosis is correct? Anybody had a similar problem with their rigs before?