engine lossing compression and knocking at about 3000rmp

It sounds like you ran out of oil and damaged your engine. That would explain the Oil Light coming on and the knocking noise. Sounds like it is time for a new engine. If you ran out of oil, you damaged all the bearings and journals which means that the engine is 'toast'. I am sorry to hear this because the 1994 Integra is one of the best vehicles ever made. You can buy a used engine from Japan for very little money. Look up ATTARCO on the Web. I did not mean that your car would not run. But, you have a knocking sound at 3000, which sounds like a piston rod knock from oil loss. You can drive the car until it won't run, but it sounds like you're engine suffered from oil loss and some bearings and journals were damaged. That is why there is a noise at 3000 rpm which is when the engine starts to really work and this is when this type of injury to an engine shows it self.