Hopefully, this may help someone. For about 2 months our 2000 S70 GLT SE had a slow coolant leak. After looking all over the engine I never found a clue as to were it was coming from so I ran over to my local Pep Boys and asked them to do a cooling system pressure test. As a part of the Pep Boys SOP, the Tech did a visual inspection prior to the pressure test. Two minutes into the inspection the Tech located the leak. No actual leak was discovered. Turns out the coolant sensor was not pushed all the way into the coolant reservoir. <p>If case you are interested the inspection cost $30 USD and if needed, a new reservoir from Volvo would have cost $58 USD.