240 General: flooding/overfueling

[523xws]

hi guys, my son has purchased a 1989 240 gl, b200 engine on Injection. The car was in daily use up till 5 years ago until the then owner purchased a torslander? and this car then sat on his drive till we collected it. we were told that the fuel pump was faulty due to it being left and that it had been replaced with another, couldn't get any life out of either so type in the code from the original into "eBay" and got a replacement, fitted it but won't start. Pulled the plugs out and there're literally dripping with fuel, checked the spark, good etc still no go. We can get it to start by disconnecting the power to the pump, it starts instantly so then we reconnect the pump and it runs rough below 3k. So could this be something wrong with the injection system or is the pump pumping to much? cheers in advance