I own a 1999 Carrera 996 and after I drive the car my coolant leaks from the back left side of the car when I park it. The coolant will drip down the back left ( drivers side) from the left tail pipe. My car never runs hot, 180 . I feel that I need to replace my radiator overflow tank. What do you think and how much will this probably cost? If I replace it myself, will it trigger the sensors?? Thank you.

 

Your coolant reservoir is cracked and leaking. Very common problem. You can replace it yourself, though it is a bit of a bear to get in and out. A couple hundred dollars for the tank, a couple hours of labor to replace it. Some dealers charge up to $700 to replace the tank. You will not trigger any sensors.

 

I have exactly the same problem on my 996 year 2000, getting a Porsche Centre to replace it in UK costing a cool £578. Oouch!!