Sixto, as usual your the tips are very helpful. Mabuhay! I will check on the aC dampers this weekend.
Mr. Watson, I will also check the exhaust. Maybe put the car in a lifter and check for holes in the flooring as well.
Mercedes Man, yes everything does smell like diesel in Manila because eveyone uses diesel... sounds like your from Manila also.
The problem is the diesel fumes in the cabin really give a bad head ache. The car has been parked in the garage for 2 weeks as the odor is unbearable during traffic. Bigger problem is if you open the windows the jeepneys get you with more fumes!
I'll check all the leads this weekend and will get back to you guys.
As always this site is really helpful specially to non-mechanics like myself.
Thank you very much again!