on the frontier that seems pretty hard to do thou, ive sprayed my engine all over so many times ive never had a problem. evadently dont spray your intake thats a DUH! llol other wise there isnt much to worry aboutsuper6turbo4 said:The only real problem with pressure washing under the hood is filling up the spark plug tubes with water. If you avoid those areas you should have no problems. Unlike older cars that had distributors there isn't much that can be hurt by water on newer cars.