This just recently happened on my modular...
Are you SURE its not your EEC\PCM?
That is the usual suspect. I've also seen the PCM wiring harness have a problem resulting in that sort of issue... do the usual "tap" test to see if there is intermittent connectivity somewhere in the harness around the PCM connection.
The relay could be at fault, that little sucker connects to so many systems its like a darn Christmas tree. I feel your pain brother, as I know that clicking sound well...

__________________
Uncle Sam
"What the hell is up with all the gauges?
Calling Captain Kirk, your ride awaits... Phasers on stun...."