super custom 2.4 1992 strange clicky relay noise

Hi all I'm new to this forum thing so please bear with me.We have a 2.4 1992 super custom which has developed a clicking noise from a relay under the dash which is making a relay in the main relay box click in sympathy.it happens when the engine is running but not under load.everything seems to be working ok no flat battery but its not consistant.any clues?thanks Doug in Devon

its not the glow plug relays is it?you usually hear them click on cold start ups,usually a few seconds apart