Fuel problem mk1 gti

Hi
Can anyone help, My golf has been off the road for 2 years after it had a fuel problem. I have had to replace the tank, accumulator, pump, lines, injectors and metering head. All seemed ok but when i was driving to my MOT today it started to loose power and will not rev above 2500 rpm, it then cut out and would not start for around half an hour. Ideling is fine the problem only comes when you increase revs.  :?  :? Also for some reason the oil warning light has started to come on but my oil is fine.
Anyone any ideas.

Cheers Chris

Did you replace all the items ir tank, pump lines etc at the same time, I only ask as I changed my pump once then realised it wasn't the problem and eventually changed the tank, but by then the crap in the old tank had done the damage to the new pump and had to buy another pump (very fickle the pumps are)