I used to wash my City EXiS 2003 Engine once in a week with Surf. No problems faced. I drove the car for 86,000 kms and it's performance was superb. No problems with the engine.
After that, i bought Civic EXi 2005, and i m washing its engine with Surf and pressurized water for the last 3 and a half years and no Problems faced MASHALLAH till today. The car is on CNG and i have driven 63,000 kms till today. Its engine has never given me any problem.
So for Honda, i m sure that it will never give any trouble but for Toyota, i cant say anything coz 1 of my cousin's GLi 2007's engine got disturbed once he washed his car's engine with pressurized water and he had to spend 10,000 rupees to get its engine in perfect running condition.