Every vehicle is recoverable, so you say it has a dema pressure within the water system, this can be for many things not only cylinder head, it could be a covered radiator, a water pump that does not work due to wear is 20 years hahaha here in Chile we repair it, we will be clear that here the repair cost is much less expensive, but independent of all this you have a simple test, the ventilator leaves the ventilator with a switch Cables and salt and see if it warms up, if it does没有,系统内部没有压力,并且水不会消失,它不是气缸盖,维修并不那么昂贵。