The blue one has noticeably the beefiest coil. The green relay has a sideways coil with direct action (no lever). But since it sits sideways it has to sacrifice some windings.

In the black relay the contact points look like a melted on blob of something. In the blue relay they are thicker, more substantial looking. The magnetic action is direct so it may mean a higher clamping force for a better connection.


I am going to order the blue ones and replace both the fuel pump relay and the fuel injector relay