Renault Megane 2005 1.5 dci cranking but will not start

[Genieous]

Good Day all, I am new here and would really appreciate some help.

I have a Megane 1.5 dci manual transmission with 149 000km on the clock. The following is an idea of how I ended up here today :

Two weeks ago we bought this car (not running) from a gentleman who said that he had taken the car for diagnostics and was told that it needs a diesel pump replaced. We bought the pump, fitted it and the car would still not start. It would crank but not start and would do this until the battery runs down. After charging the battery it then showed the error check fuel filter. Which we did and replaced. Still not starting.
After much research online we checked the timing belt and pulley but these were fine. We eventually found out that the relay needed to be replaced as the glow plugs were not lighting up. We replaced the relay and now glow plugs are working. We have checked the injectors which all seem to be working fine. We have primed the bulb to make sure fuel is going through as it should. The battery is also fully charged. We have removed the tdc sensor, cleaned off the grease but still NO luck.

Please excuse some of the terminology if it is incorrect as I am a woman and have explained to the best of my understanding☺

If there is anyone that can help. PLEASE. I think the mechanic is ready to throw the car over my back wall.

[camer000]

Have you tried plugging in a diagnostics device to see if there's anything else that the car thinks is wrong?

[q292u]

Something like this. Less than a fiver.. works with android phones & tablets..
https://amzn.to/2cO00j1