1997 f350 7.3 My #2 relay in the fuse box under the hood chatters I cleaned all fuses and sprayed holders with contact cleaner the wts light will not come on till the chatting stops I changed the relay out but it still chatters but not as long as it was doing than it stops and the wts light comes on and I can hear a click in the start relay on the fuel pump then it will start Any ideas why it chatters I cleaned all wires on the start relay also

 

Chattering relays are a SYMPTOM, not a cause. Usually a symptom of low voltage. LOAD test BOTH batteries, in isolation of one another. Check all major power connections - battery terminals/posts, main battery cables, battery grounds at the engine block, main accessory power wire from passenger battery+ to distribution point at starter relay.

The starter relay is on the passenger side fender. The fuel pump is purely mechanical.