Some b*stard of a previous owner thought a pressure wash would be good for mine too.
Now my engine bay is full of rusty nuts and bolts that break rather than undo.
So my engine bay detailing removes the 'elbow' from 'elbow grease' in a (probably vain) effort to stop the ones that remain from going rusty.
Yes a nice clean engine bay looks good, but it is no good to me if you can no longer adjust a belt tension or remove an engine mount coz the bolts are rusted up. Or bolt the battery down (which will fail at the next MOT).