Possible causes:
1) Faulty fuel system relay - see FAQ or location in relay tray
2) Faulty Radio supression relay - Located no one or the other shock towers, black about 1" by 1.5" by 2". May be two identical relays. The other is for the coolng fan, swap them and see if the problem is fixed.
3) Faulty hall sensor in distributor or speed sensor on top of the transmission. Car will only have one, but not sure which is on '89 740. Signal output from this sensor is required for the ecu to "turn on" fuel pumps and ignition.
4) Fuse for fuel pump
5) Ignition power stage - driver side inner fender
6) busted timing belt
7) ecu faulty
8) bad coil

If the fuses are OK, check to see if the cam is turning when cranking the engine - remove oil fill cap and observe cam while assistant cranks the engine.

Determine if you have spark and if the main fuel pump is running. Fuel pump can be checked by listening. It is located under the car slightly behind drivers seat. Spark can be checked with old spark plug - lay plug on engine and connect to one of the ignition wires. Observe while cranking and you should see a bright blue spark at the electrodes. If no spark and no fuel suspect one of the relays above or the hall sensor.

You should also check the injectors while cranking. Listen to them for a ticking sound while cranking. Use a mechanics stethascope or the tip of a long screw driver held to the injector and the handle to your ear.

Report back your results for further diagnosis.

Dan