2.3L ('83-'97) Duraspark II conversion problem

[85_Ranger4x4]

I think this is where I'm at now - I never even tried to use the original TFI coil for this setup and have only attempted using the round oil-filled coil, and even after installing a ballast resistor it still acts the same way. I also tried powering both the coil and the Duraspark module directly off the battery, same behavior. What am I going to have to rewire and do otherwise if I yank the ECU out?

Mine was a 2.8... and this was like uncomfortably close to 20 years ago.

The ECM getting tach signal was the only issue I had. Computer has nothing to do with anything as long as you don't have an A4LD or cruise control.

I think cruise just tells the ECM when you are using cruise and it may pick a different algorithm or something. I didn't add cruise until after I had ripped the ECM out and it works fine.

 

[TheAbstracted]

Certainly the ECU is looking for a signal from the TFI. But what will it do if it doesn't see the signal? It's not hooked to anything so it's crippled and can't do anything about it even if it wanted to. On a efi system it would turn the electric pump off, but you have a mechanical pump. And you have the ignition wired to the keyswitch. You have spark and fuel, the computer can't control any of that anymore.

Welp, I think you might have just solved it for me. I don't have a mechanical fuel pump, I did not install one of those when I did the carb conversion. Instead I removed the high pressure pump and in it's place I put in a little Edelbrock fuel pump and reused the wiring. Probably won't have time to get to it and test until this weekend, but I feel like I should have thought of that sooner. I'll see how it does and report back, thanks!