About 15 miles after a timing belt change, the oil pressure light started flashing in my 2004 VW Passat. Coolant was also leaking. Towed back to garage and they replaced coolant tank. Drove it away and oil pressure light started flashing again. Towed it back and they replaced something else, something having to do with the oil pan maybe? There was no charge for either. Drove it away and light started flashing again. They said the sensor must be bad and to not worry, keep driving it, they would get back to me with a quote on oil pressure sensor. Took it to another garage who told me the sensor is working fine. Does anyone have any ideas as to what could have happened that would cause the oil pressure light to go off?