I have been having some intermittent engine cut out problems. Today I verified it was not my fuel pump as I ran a test bulb from pump and drove the car. When engine tried to cut out test bulb stayed on.Waanted to see if I was losing spark so I went to the coil and grounded a test light to the post and took probe end and touched the tachometer side of coil. When I did this I got some sparking and the engine would hesitate/sputter just a bit. I do not think this is normal, is it?

Check the Coil wire at the distributor. It can loosen up and drop down a little.
Make sure it is tight and not backing out. Since it does connect UNDER the cap.
It is easy to miss.

If it is the coil, and/or you decide to replace it, go to Checker/Shucks/Kragen. That's where I got mine for $43. It's the Niehoff brand and is a direct replacement. A heckuva lot cheaper than the Bosch original. (As a added bonus, if you're dressing up your engine compartment, you can 'polish' then exterior aluminum casing!)

Just trying to save you a few bucks...

- Al

I think you tested the presence of voltage to the pump but not the pump itself.

I once tried to apply a test light to the neg coil terminal and it stopped the engine. I concluded that the relatively low resistance of the bulb (it was a tail light bulb) did not allow the voltage to rise to 12V in between the \ negative going driving pulses from the power stage. Your test bulb may be smaller wattage (higher resistance) and it is allowing the engine to continue running. I think your result is normal.
To check for presence of pulses from the power stage why not just watch the tach itself. It will plunge to zero faster than the actual engine rpms if spark pulses stop.

When engine cuts out or stumbles tach. doesn't drop. Is this what you mean?

Also, engine will cut out only when I try to accelerate. Idles fine, starts fine. Things replaced so far. Throttle switch, O2 sensor, Fuel pressure reg., a lot of engine wiring, main fuel pump, intank pump < 1 yr.old as well as fuel pump relay. Throttle body cleaned, new wires, distrib.,rotor, plugs in good shape.

If tach stays up then it may well be a failing coil?
A clogged fuel filter can restrict flow causing drop in rail pressure when there is a demand for more fuel.
Does engine stall and restart or this just a momentary event.
Can you get the car up to speed at all?

Engine will not stall, if I accelerate very, very slowly I can get up to speed. If I try to accelerate quickly-nothing, I can have pedal all the way to floor and get no response except some backfiring under hood. Let up a bit and accelerate slowly and no problem. Luckily there are no hills here. I can get up to speed as long as road stays level. Problem used to be more intermittent, now it is constant I think. Could the fuel filter cause an intermittent?

Still trying to isolate problem. I might go ahead and replace coil and fuel filter when I get a few extra $ Thanks for the reply's.