Fuel pump replacement 1986 bmw 750 k - BMW Motorcycles

It sounds like either the throttle position sensor or the mass airflow sensor are bad-the TPS can be checked with a digital meter, it should give different voltage readings as the throttle is opened with the engine off, key on. The MAF can be cleaned with MAF cleaner, or will need to be replaced. Another, although less likely possibility is a clogged fuel filter.

Check the Air Mass sensor and Oxygen sensors.

Fuel pump may be getting weak. If pressure is not high enough the injectors wont open.

Verify TDC sensor

check wires, and fuel pump, if those are fine it may be the electronic control unit

You will need to check for fuel pressure or dirty filter. If you do not have fuel pressure; be sure to check fuses or any relay pertaining to fuel pump (if electric). If fuses and relays are good check or replace fuel filter. If the fuel pump is mechanical disregard fuses & relays and check or replace fuel filter. If this does not resolve the problem then the problem could be the fuel pump if mechanical, If its an electric fuel pump it could be a fuel pressure regulator, fuel pump, crimped fuel line or other wiring issue.

These are the most common things I run across, oh, a crimped fuel line can cause the problem in either case electric or mechanical. Hope this helps in some way, been awhile sense I worked with an older car.