I'm helping a friend with an 84 Accord Hatchback. He had blown a head gasket and when we were putting it all back together we noticed that a vacuum port on "Thermovalve A" had broken off.

Thermovalve A is a vacuum switch that screws into the intake manifold under the carb. It points directly back and is the thermovalve farthest on the left.

I found a number of used Accords somewhere, and pulled a couple of these valves off. The two that I got off the parts cars were yellow, while the original was blue.

Does anyone know if there is any significance to the colors on these switches?