Thanks for reading. I am a new member . Current problem with my daughters 88 240 dl.. Last month replaces the fuel pump after getting a ECM from E-bay and both main relays at the local junk yard. After doing the pump it ran and I swapped the 3 parts one at a time to confirm they were good. It started right up with each one. I kept them aside for spares and ran the originals. 2 weeks later it died on her. Cleaned carefully the 20 amp fuse holder under the hood. Cleaned all the fuses and the whole fuse box. Swapped each piece one at a time and no difference. I get power to #4 only while I turn it over and then power is out. I jump #4 and i hear the pump. Any help would be appreciated. I was going to get the ignition control module next.

 

Instead of swapping parts randomly - how about diagnosing what's wrong.

Start with basics. An engine needs compression, spark (at the right time) and fuel (at the right time)

Does the engine have compression? Is the timing belt spinning the camshaft?
Does the fuel pump turn on? (can you hear it buzz when you bump the starter - it should run for one second). If you can't hear it you can jump the relays, or more easily, pry the covers off and hold the relay points closed to manually turn the pumps on.
With your $5 test light does one of the terminals on the coil flash when engine is spinning over? Or is there a spark getting coming out of the coil ? Carefully hold the coil wire near a ground point and look for a spark.

Once you determine what system is not working - address that system only (instead of just replacing stuff - that gets very frustrating)

 

I have spark at distributor. Number 4 fuse pulses when I turn car over. I only got the parts to try to eliminate possible problems. They were used and cheap, good for spares.

 

Sorry don't know what "Number 4 fuse pulses when I turn car over" means. Never used that as a diagnostic parameter in my 40 years working on Volvos.

But If you have spark (at the plugs, a shorted rotor button/cap is possible if no spark at the plugs, and I trust the spark plugs are in good condition) - you can spray some starting fluid (ether) into the intake to see if it runs for a few seconds. If it runs you will have eliminated the ignition system as being a problem (specifically the ignition system module "you were going to get next")

If it run on ether - an easy fuel system check is to plug in your $9 noid light to see if the injectors are getting a signal. Remove cover from the fuel system relay and watch the contacts close and power on the computer and the fuel pump when you cycle the key. Listen for the fuel pump to buzz when you bump the starter or manually close the relay contacts.

You probably don't have a fuel pressure gauge but you can verify fuel flow (but not pressure) by disconnecting the feed hose at the manifold (dumping fuel into small container) and activating the pumps. Should be a steady stream, with no air bubbles in it. Air bubbles in the stream could be low/out of gas or a broken feeder pump hose. (i've had many cars towed in for no start - because they had no fuel in the tank)