Need a computer

[My90bluebrick]

We've had our 90 240 dl sedan now for a few yrs. And it's been a great car. But there has always been a problem with the ECU. Where you have to rig the fuel relay to get it to work correctly (the car came that way) and we cannot get the fuel side of the diagnostic to work. But other than that it's been great. Well it went down recently. It would barely run. We changed tps, maf, oxygen sensor, air idle control, fuel pressure regulator... it runs but not good. Idle is not good. Low power. Some times it will pop like a back fire. It's jetronic. I've went over it a couple times with cleaning of grounds and what not. What am I missing?? we would like to get another computer so we can atleast be able to get codes... Please where can I get either new or rebuilt with gaurentee ecu. I love my car and hate to give up on it. Help!!