GL420 2007 fuming

wofakwabena

I love Mercedes Benz, I bought a used GL420 diesel from Germany to Ghana. Eversince, the car arrived, it has been unpleasant fuming (whitish smoke) from the exhaust sometimes. Several mechanics are saying that this is a common issue with the GL. Since last week, the check engine symbol keeps on appearing even after a thorough check.
Has someone had such experience before? If yes, what can I do?
Thanks

stever

I wonder if it's related to the quality of fuel available there.