Hello to all. The car is an Xsara 1.6 break (kombi), year 2000 with 72000
km on clock (Automatic AL4 transmission).  I have noticed a few times that
while cruising at 100 km/h the speedometer falls for a second down to 0
km/h and then comes up again like if nothings have happened. One time,
when it was raining heavily, the S (sport) and * (snow) lights at the gear
diagnostic panel lighted up, blinking, and after 20 km came off again,
Speedo needle went down and up again a few times. While all the above
happened, the car and the transmission behaved normally (except that while
transmission lights were blinking, it was impossible to shift to 'Sport').

What's up with her? Is she going to be sick? Thanks in advance – Mike.