1987 5000S lack of power
 

I recently acquired a 1987 5000S and I have almost no knowledge of this car. I have been a Volvo tech for five years but this car looks alien to me. It has been sitting for a long time, it starts and idles fine but once you try driving it has no power (like it's not getting enough or too much fuel). It is apparently "fuel injected", I see an apparatus on the left fender that I'm wondering could be the fuel pump and then metal lines feeding the cylinders. Someone has replaced the fuel filter but that seems to be it. Any information would be much appreciated.