Look on top of the pump where the high pressurse hose connects to it. I had a simular prop and I had a a fracture just under the bolt on the fittings. the leak ran down the hose and puddled under the car in the center. Over time I was finally able to see the build up and figured where it came from. I bought the hose from Auto zone for 63.00. It was OEM but didn't come with the sensor. I highly suggest you check it soon cause this will harden the wires on the sensor, and when you go to replace the high pressure hose (if its the prob) the wires will be brittle and brake (been there done that). Its not hard to replace the hose, just ackward because lack of space when snaking the hose back in. Took me 3 hours.