How can I restore the ecu if battery has gone dead and car is in limp mode now?

What is your question?

My 1997 A4 quattro 1.8T was parked over the summer and I did not realize the battery had died. It starts fine, idles great but won't rev above 2k or so then drops out and comes back drops out and comes back. I am assuming the ecu or fuel inj. comp. eeprom has lost it's program.