The day after I washed my car, it was very hard to start. It was a chilly day, but not real cold. It only has about 13,000 miles on it and has run perfect since day 1 and has had regular maintenance, garaged, same brand and octane gas, etc... I really had to pump the gas and on about the 3rd attempt it started up. Once I got it started, it ran rough for about 30-45 seconds then smoothed right out and has been fine since (only driven twice since then but fine so far). I do remember accidentally spraying a bit of the hose stream into the tailpipe (not directly, but in the course of rinsing some collected soap suds out) and wondered if that could be a cause. I mention that because all else was exactly the same as every other wash. I don't know if I got water somewhere that it shouldn't be and it just needed to be run a bit to work it out or what.......not familiar with intricacies of cars...thanks for the input/help.