More than a couple of us have run into engine problems after pressure-washing because of water getting up under the ignition pack seals and down into the spark plug tunnel. So you ened to be careful of that. It's easy to rectify though - just remove each ignition pack and dry out any water that's gotten down in the hole.

That's the only problem I've had. It would be best to wash it in the morning and let it sit with the hood (um, sorry - bonnet) up until the engine bay dries out.

Good luck!