Mr. Monk Meets His Dad - S5-E9
Other mistake: When Jack Monk is filling up his truck, the numbers on the pump don't add up right and keep changing. The cost is $3.599/gallon, but in one shot you see the sale price reads $93.78 for 28.348 gallons. The sale price should be $102.02. But in a later shot, he's only pumped 27.126 gallons. Then when he hits $100 sale price, it's for 31.259 gallons ($3.199/gallon) but in the next shot it reads 27.719 gallons.
Answer: Notice also that in the opening credits scene when he is touching parking meters her also wipes his hand on his clothes each time he does it.