anybody have any rough wiring diagrams atall please,should i run an earth for the pump straight to the battery,would a 20amp fuse be ok,should i put the immobiliser before or after the relay,where do the other wires go from the relay

 

Wouldn't have thought the earth wire for the pump needs to go all the way to the battery, just a good solid earthing point near the pump will do.
20A fuse should be fine for carrying that kind of load.
As for the relay wires,
30 = Battery positive
85 = Earth
86 = Switched Live
87 = Output to consumer

 

which wire would be best to put the immobiliser onto,would it be ok on the battery wire or should i put it onto the switched live from the ecu,forgot to say its efi sorry so dont know if this makes any difference atall

 

also the earth to the relay would that be ok to run to the battery or just try get a decent earth near to the relay

 

The wire for the immobiliser i would say would be best put onto the live wire feeding the relay so it cuts the power at the first available source, ie the relay and not the pump.

The earth for the realy wont need to go all the way to the battery and will be fine on a suitable bolt or screw hole near the relay, i usually run the earth wire from terminal 85 on the relay and earth if onto the bolt or screw i use to secure the relay onto the body.

 

would it be best to use a new relay or could i use the original,if a new item is the best choice how do i know what relay i need when i go to buy it

 

Your original relay will be fine to use mate.

 

ok cheers for that much appreciated

 

No prob mate.