fuel injection problems on a 77 bmw 630csi

I have a 77 bmw 630csi that im having trouble with the fuel in injection when I turn on the car and i accelarate the car dosen't respond like 2-3 seconds later can someone tell me whats wrong with it
thanks

If it is injected it is an L-Jet.

Here is a link to the troubleshooting page at firstfives.org.

http://www.firstfives.org/faq/ljet/jetronic.pdf

My WAG is the fuel pressue regulator.

It has a vacuum line connected and if the throttle is opened and the intake pressure drops the fuel pressure should go higher.

Later,