the car is a 1997 c200,4 cylinder u.k spec car.

has 67,000 miles on the clock and been serviced regularly

today while accelerating after a cold start,the car began to misfire and after half a mile, it began to run properly on all four cylinders.

what could be causing this?

only thing i can think of is that i had the car jet washed yesterday from the outside (not the engine) .

could water have got into the electrics to cause this or is one of the coils faulty?

any comments welcomed