Here in Virginia . . .
they are switching from the kind of traffic sensors which are buried in slots in the pavement to some sort of radar or laser devices mounted up on the horizontal traffic light supports to tell the light's computer whether there is anyone waiting in each of the lanes in each direction (some people have been mistaking them for red light runner cameras, but that's not what they are). I wonder if they could be sending microwaves which might confuse your computer or your crank sensor? I do get nervous about being microwaved every time I stop at a light, but they certainly can't affect my '85 300TD.
Do you see any small tubes on the lights? They look like those cameras on race cars on TV.