The car is on 85k miles but only the last 5k or so in my ownership. Not sure what the average speed/ fuel consumption would have been. Its been a city car most of its life though so its quite possible the fuel pump has done over 5000 hours. 20mph average speed over its life probably would be about right so its over 5k hours.

I'm happy enough to throw parts/money at this... but the harder thing is having confidence that its fixed because the car is working fine again right now.

How do I to hidden test 6? Can't seem to find the instructions for that. Do I need something to plug into the OBD?