91 Civic 1.5L Stalling problem...HELP!

I have a 1991 Civic hatchback 1.5L. I recently bought it and replaced the engine with a used jap one. It runs great but has left me stranded 3 times. Two times I was driving down the road with no problems and the car just shut off and coasted to the side. I try starting it and it will turn over and over but acts like there is no spark. The first time a mechanic said he tightened the rotor, the second time he said it started for him and he could not find anything wrong. Another time I jumped in to go to lunch and it would not start...again, just turn over with no spark. Could this be a bad Distributor? Bad ignition switch? Bad fuel pump???? Any suggestions would be greatly appreciated. Garry

Main relay... get a known good one and change it, see if it ever does it again, if not, that was your problem.

Keep the old one, get your computer g33k buddy to solder it, so you have a spare... b/c guess what will happen to the new one? You got it!

Thanks for the thoughts....I am nor clear on the Computer part...what are you suggesting? Also, where is the main relay located? Thanks again

get a friend with soldering skills that can redo the joints in the old one for you.

The main relay is just above the hood release, on the d-side above the kick panel.

The "Main Relay" is actually called the "Main Fuel Relay" at Honda. This would not cause a no spark situation. When the Main Fuel Relay is on the way out it will cause no starts usually on hot days after it has been driven because you are not getting fuel. If it were the "Main" it would not just die while you are driving it. It sounds like your distributor to me. You said you have no spark which means it is either the ignitor or the coil inside the distributor. Parts stores do sell these parts separately but they are expensive. Go to autozone and get a dizzy, If it doesn't work they will let you return it(Lifetime warranty).

I missed the part where he said it shut off while driving... so yeah, you're correct on that.

Check all your grounds too, specifically the one at the thermostat, and the one under the battery tray on the chassis... it's part of the (-) battery cable.

Thanks for all the tips. I just got the car back after replacing the Distributor. So far so good.....Thanks again, Garry