Hi gary welcome to JA
Would a wiring diagram be of any use to you?
Fuse 26 is fed via fuel pump relay K20 have you tested the pins in box for ignition and battery feed and ecu earth?
Tiga has had several faults for non starting/poor running faults such as ignition coil earth connection, coolant sensor wiring and sensor failure.
Let me know results of testing relay circuit so i can help you
technician & lecturer
28+ year experience cars, trucks & bikes