pressure washer for washing ?

anyone that uses a pressure washer or has had experience with them, can you answer a question for me please? I was given a Ryobi gas 3100psi pressure washer and I want to use it to wash my truck ( I know this isn't home improvement but more the washer ). do you have to always have the trigger pulled or is it safe that I spray leave the motor running wash then pull the trigger? meaning the water is not being used but the motor is ideling. or do I need to shut the motor off in between and always re start the motor? don't want to damage the motor. would I be better using an electric pressure washer for this use? I will post this in detailing thread too
thanks david

 

It's OK to leave it running. However, I would not use it on highest pressure to wash truck. Or at least keep it back quite a ways with a wide pattern. At 3000psi it can work like a sand blaster with dirt on the truck. It can also lift paint if it finds a small chip to get under.