Volvo s70 1998 model failing to start

[Yappy]

My volvo S70 98 model is failing to start. It was running well before, but the only problem was that of continuous smoking of which i suspected the turbo to be the main culprit. I removed the turbo and evidently there were signs of leaking oil, hence continuous smoking. After fixing the turbo i then put it back after about 3 months and the engine could not start. In some instances it would sound like it is about start, and if it does it will just be for two seconds and die. I checked the fuel pressure, while trying to troubleshoot and the pressure looked fine to me, meaning that the pump is suppling adequate fuel. All the injectors are working well. I also checked the plugs, and the earth everything seems fine. Now i don't know what to do next considering that the vehicle was running before i removed the turbo. Please could anyone help me on this issue.