Starting relay...

… I think it's on it's way out    after I drive her for a bit, if I stop the engine and then try to start again, I sometimes get nothing (not even a click when I turn the key). I had a major case of this when filling up with petrol last night, I was checking fuses to see if that was the prob (obviously jigging the relays as I checked the fuse) and she then started and off I went. Got home and tested it again, got nothing until I jiggled the relays then she fired up fine. My question is: What relay is it that I need to look at?  :dontknow: