epc light
 

hi guys, im new here.. i have an audi a4 1.8t 2004.. last 2 weeks or so epc light coming on and its taking time to start sometimes, brought it into the garage and computer said it was water pump sensor, they didnt have there but said come back in a monday, but today the emissions light came on to and the car wouldnt start at all, my question is would the sensor have anything to do with the cat???? or is this a seperate problem...
any help on this matter guys???