Engine management light - orange

[copas]

Car was running fine until sunday. I had washed the car with a normal household hose (not power washer). The next day the orange engine light came on and the performance changed dramatically. Poor starting, low power, slight stutter, poor acceleration. One day later warning light disappeared and fully back to normal. Obviously there's lots of comments on the web about getting water in engine bay and the consequences but the car washing was a normal household pressure hosepipe. Although I did aim at the grill a few times as I thought the air inlet would be angled or not directly behind the grill. Couple of questions you may be able to comment;

1 - could the wash have such a drastic effect on the lambda sensors; pouring rain does not and it drives heavily into the front grill

2 - can the megane go into limp home mode when the orange engine warning lamp comes on (I would expect it with the red spanner engine light)

3 - is the air intake behind the grill (the engine air intake disappears behind the battery but I can't see where it goes on from there)