Hey thanks ulit for the info.

I also got some advice from friends, and I wanted to share them for the benefit of those who have or will be having car a/c problems.

Pag nawalan ng lamig a/c, the following are possible causes:
>> walang freon
>> leak in the system (like hose or sa cooling coil) kaya nawala ang freon
>> broken or clogged expansion valve
>> broken or clogged drier/filter
>> broken or leaking compressor

Medyo swerte sa napiling kanto a/c service center dahil mabait may-ari. Unlike four others I visited na may quotation agad ni hindi pa nila hinawakan kahit ano, they tested everything at kung magagawan pa ng paraan they give you options. Of course nag-leak test ng mga hoses and pipes, and since ok naman, they checked the drier, ayun barado daw kaya nde pumapasok lamig. Good thing hindi nasira compressor because of pressure, kundi mas malaki damage. Beyond repair ang drier so pinalitan. Then they leak tested the evaporator and checked the expansion valve. Medyo barado rin expnasion valve pero nagawan ng paraan. But the evaporator had a few leaks na hindi na rin marerepair so we had to replace it.

Anyway, sulit naman ang gastos. Ang lamiiiggg!!!