I had a fair bit of work done to my 1999 Subaru Legacy last week with the main fix/problem being a timing belt replacement. Additionally they replaced oil seals, 2 hose clamps, the radiator cap, the water pump and the thermostat. They also topped up my coolant, bleed the system and checked for any leaks at the end.
However, I drove the car for the first time today after getting it fixed for around 6-7 minutes with the temperature gauge remaining normal but when I arrived home I noticed a constant stream of clear/light grey smoke coming from the hood. I then opened it and found the engine smoking at a moderate level predominantly from under where the cylinders are, this lasted around 4-5 minutes. My coolant levels have not dropped but there was a slight hissing coming from some of the hoses, leaving a minuscule amount of coolant (a few drops) on one of them which has still never happened to my car before.
My mechanics are very trustworthy and I was told to 'keep an eye on the water levels'. If anyone could help me diagnose the problem or come up with a solution that would be very much appreciated as I am currently too scared to drive.