I bought a 1999 Chevy Tahoe and I noticed white smoke coning out the tailpipe. Could it be a blown head gasket or O 2 sensor..Please help me figure this out..I had a tuneup and oil change done
White looking water vapor (smoke) on engine warm up when it is cold outside is normal, but white smoke that comes out when engine is warm is not. Generally white smoke is antifreeze and can come from cracked cylinder head, head gasket or cracked block. Check to see if you are losing any coolant.