i am driving a 5 years old viva and having a terrible problem now. the air cond working fine, but out of sudden it will come a bad smell like those petrol black smoke smell. but when i turn off the a/c, the smell will gone, and turn it back out of sudden it will come back. I had visited few garage and none of them know whats wrong. Presure checked, its working good. Pls advise.