i've seen people use it before, especially on cars that looked like they haven't been touched in a year, so i was just wondering if its ever ok to use a pressure washer

 

Certainly, just dont get real close to paint chips or moldings/trim areas.

 

If I may add to the last post-

Pressure Washer:
Electric powered high-pressure washer's can be used everywhere that a normal mains pressure hose would be used, but you should take a few precautions with there use. Beware of forcing water into areas were it can't drain, and don't hold the nozzle too close to paint surfaces for as well as impact damage an excess of water pressure could damage paint surface, it can also remove stripes and vinyl graphics.

Be careful when working with the pressure hose nozzle close to the vehicle paintwork, or while working in confined places like engine compartments as it could recoil and cause impact damage, try to keep a three or four foot distance and use the wand at a 45 degree angle They are an ideal tool for the cleaning of fender wells and undercarriage, and for the removal of road salt from these areas.

 

make sure to use the delicate nossel and also not to get to close to the car.