Howdy peeps, my apologies if I've posted this thread in the wrong place. Mods, feel free to move it around if needed.
I've converted my EFI 1985 105/115 2.0 Spider to carbs - Runs great! But the car is still operating with both the Bosch ignition and fuel ECUs hooked up. I would like to remove them since now that the car is carb'ed they are rather redundant. I know that:
Cheers,
--Andre
I've converted my EFI 1985 105/115 2.0 Spider to carbs - Runs great! But the car is still operating with both the Bosch ignition and fuel ECUs hooked up. I would like to remove them since now that the car is carb'ed they are rather redundant. I know that:
- If I disconnect the fuel ECU and leave the ignition ECU connected, the car starts but runs really poorly. So the fuel ECU might still be controlling fuel pump activation
- If I disconnect both ECUs or just the ignition ECU, the car won't run at all. Correct me if I'm wrong, but the ignition ECU controls spark unless I go with an aftermarket distributor
- I know the drive relay is responsible for the operation of the pump somehow
- In the process of plugging/unplugging stuff I've successfully and thoroughly fried the main relay. Fear not, I've removed the corpse of the relay from it's harness, and the car still runs with it disconnected. So I know it does nothing in my current configuration (I believe it controls the now non-existent fuel injectors)
- Using a forum search I've found the following quote from Papajam (RIP):
Does anyone know what I should jumper/ground so that the fuel pump operates without ECU control? I get that I may not be able to delete the ignition ECU, but any guidance there would be greatly appreciated as well.Drive relay (short version);
When the key is on, switched power is supplied to terminal 15. The input terminal 30 (fused from battery) and output terminal 87 (to fuel pumps) contacts are open. Fuel pumps do not operate. When starter is engaged, power is supplied to terminal 50. This closes the 30 & 87 terminals to power the fuel pumps. At the same time, an ignition pulse is received at terminal 31b. When the engine starts, this ignition signal keeps the 30 & 87 terminal contacts closed after power to terminal to 50 drops out.
Cheers,
--Andre