i went to a mechenic for tuning and he said my car's engine is weak and its giving smoke but when i checked it there is no smoke, oil is ok ive seen it sometimes giving a little smoke of white color but i think its CNG smoke or something dont know about it but right now i done see any smoke and i can see water dropping from silencer ? please someone guide me should i get my engine checked from someone else or this water thing is enuff that my cuore's engine is in good condition??