Technical fiat uno 70 1400 injection

[b555]

sometimes (can happen once a month) the engine seems to bog down and when turn the switch off and start again everything is ok ,somtimes takes a second to respond I tried to replace wires fuel pamp maybe is the module where is the location of it?

10x
b555

 

[SteveNZ]

2 relays I think on the LHS of the engine bay