Umair,
I've used a Denso (after market) A/C in a 2004 Mehran, it was hopeless. But then i got the complete unit serviced and got DuPont gas filled. One thing to note here is, the inner vents/ducts of the AC channel were clogged with leaves and stems, I would assume it is one of the major factors for Mehran's A/C losing it's efficiency over time. Anyway, once the whole unit was serviced it was no longer the same case as before. It was infact really impressive afterwards. If you are in Karachi, the best place to go to is Khalid Autos, behind PIDC. It's on MT Khan Road, shortly after Caltex petrol pump, on the same side.
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