 Mike talked about a number of different symptoms, including coolant loss with no apparent leak. Well, this points to a failing head gasket, which, if left untreated, can lead to serious engine damage. It may allow coolant to mix with the engine oil, and it could even reach and ruin the catalytic converter or oxygen sensor, leading to a very expensive repair. Another consideration, head gasket failures usually occur on older vehicles. So, in inverted commas, you could say the fixed