Marty: You have one of those hair pulling intermittant problems which requires some sophisticated diagnostic routines, however if you are really going to try and fix this problem yourself, stay with this forum and be ready to invest in some diag. equipment. Do these things: 1. Check fuel pressure at fuel distributor or spray bar inlet rail, buy or borrow a fuel pressure gauge that goes to at least 100PSI. You need a "T" fitting to do this test, 3/8" on top of the "T" side, 5/16" to the pressure gauge side. You need a steady 75 to 85 lbs. PSI for good running. Also check the volume, its about a 1 quart delivery in 30 seconds. Hose clamp all the fittings, as the 80lbs of pressure will surely pop a test hose off its fitting. If your pressure drops at any time during the loss of power, replace or service the fuel pump relay first. A tell tale test is to run a pair of wires from the pumps and into a VOM, set it for DC volts. you must have 13.XX volts solid at that point, if it drops down during the power loss, its the pump relay. If you have a module on the left side of your battery compartment with a knob marked 0/1 on it, this is the MAS module. This knob actually retracts the module from its socket.The fuel pump relay is inside of this unit. IT CAN BE SERVICED. If you have a seperate relay for the pumps, just find it and change it. If there is no power droppage to the pumps, do an entire fuel sys. overhaul. Clean Pickup screen, (large allen socket plug in middle of tank, you will need a new O-ring), main filter, check fuel accumulator, fuel pressure regulator. If you monitor the fuel pressure directly from the pumps and it fails, its the pump (s) or accumulator. if it drops when hooked between the inlet and pressure regulator, its the regulator. Generally, the fuel sysems are bullet proof, and If you find no faults with pump power and pressure, I would do: Ignition overhaul, plugs cap rotor wires, and coil... Also replace your OVP relay. The MB Ign coils are the worst, especially the older ones with sheet metal stamped center sections. Go look at the color of your spark, it must be whitish blue, not orangy red...... be patient, you'll find something eventually.....
If its the CPS, the tach will drop down even though the engine is running. It tests: 750 to 780 ohms, and .480 to .505 Volts AC during cranking. They do sometimes fail even if they test good with the VOM. If you have no spark at any time, it could be the CPS. Also check the rotor adaptor plate retainer bolt, these adaptors get loose too.

go here to learn where your modules and relays are located
http://mb.braingears.com
Go here for parts: www.***************
http://catalog.peachparts.com/
dave
dave_rose69@yahoo.com