I have a '95 EX that runs fine. Sometimes when it is cold and just started up, the headlights and interior lights and tachometer will surge up and down about once a second. You can see the headliights, radio and dash lights brighten and dim, brighten and dim, brighten and dim. The Tach will go up about 500 rpms and down about 500 rpms, up 500... The peak rpms coincides with the peak brightness of the headlights and interior lights. Usually only happens during winter/cold weather and then only when first started for that day and always intermittently. It may go a month between episodes and it may go a week. After the car is run and shut down it will not do it on the restart that day. It's like whatever it is, once it gets warm, it works fine. Any ideas?