Without knowing a whole lot more or what was done. Many times a relay will sorta burn it's contacts and intermittently go on the fritz, a jolt would make it function or not function. It's not a real expensive thing to throw at it (if it even has one) Your owners manual or your fuse box cover may reveal it's position.
This may not be it, at least you'll have a fresh new one!
My Dad, found that slapping his trunk lid, would get his fuel pump operational for a good while, till the Fuel Pump Relay became "Terminal" in his '86 T-Bird!
If you have no luck finding it, let me know, I'll dig deeper
Let me know your situation and status
Monday, July 4th, 2011 AT 3:33 PM