Guys I have never washed my cars underneath with watter ..

is it ok to put the car up in a ramp and wash it with a high pressure watter gun

Thanks

 

If you've ever run through a puddle of water, I imagine it will be similar...

Joking aside, I would try to avoid directly spraying electrical components.

 

Really bro? Really? Really REALLY? Wash it man. Just don't aim at the electrical connectors with high pressure water though. Focus on the non electrical bits.

 

I would not be power washing mine that for sure. There is a very high chance that water can be forced into breather holes into the diff and transmission. Also if water gets into pulleys and bearings they will fail pretty fast.
Normal hose pressure is okay.
And why do you need the underside of the car so clean anyway?