E30 Zone

no fuel coming through fuel regulator ,at end of rail ,25i 86 high comp engine ,can you swap a regulator off 18i 1989,or can it be cleaned out

It could be a coupple of things first I would check if you have fuel in the tank but I know you aint stuped so then I would move on to the fuel pump and turn egnishon on and see if you can hear a buzzing sound coming from it and iff you can't then you know its that then I would go straight to the engine and find the fuel line and if there isent then it would be the fuel line then you should get fuel rail or injecters and swap them because that would be the only thing it could be

Fuel pump is only live when the engine is cranking.
Check,using a 21w bulb across the pump terminals,that power is reaching the pump whilst cranking the engine.
No power?
Check the fuse and the fuel pump relay.
Power?
Pump shagged,tap the top with a Birmingham spanner and re-check,if it now works it will fail again very soon,so replace.

If the pump tests fine,next port of call is the fuel filter,is fuel reaching it?
Is fuel leaving it?

Then you are onto the fuel rail,is fuel getting here?

If there's no fuel coming through the pressure regulator, the most likely reason is that the fuel pump isn't developing enough pressure to open it, for various possible reasons, ranging from a clapped out pump, through a fuel leak, to the pump not being powered.
The FPR itself isn't likely to be faulty in a way that gives excess pressure.