Engine Cooling problem
2001 Chevy Malibu 6 cyl Front Wheel Drive Automatic 150000 miles
I have a coolant leak that cannot be found by the shops that I have taken my car to. After driving for a period of time, I start to smell the coolant and once stopped I can see steam or smoke from what I presume to be the leaking coolant burning on the exhaust. I have already replaced the lower intake gasket (common problem I understand) around 85,000. The shops I took it to said they cannot find anything wrong. I only notice this leak in the winter months when I need to run the heater, but the mechanics assured me that there was not a leak in the heater core.
I am stumped and in need of suggestions. Thanks in advance.