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Another FI question for those that have done the conversion


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I am just seeking some sort of confirmation on the various power supplies that would be needed to get the FI conversion up and running ..what I understand to be is:1) 12v from the battery connected to the fusible link..2) 12v, ignition key-on to the ECU..3) 12v ignition key-on to the ignitor..4) 12v ignition key-on to the fuel pump relay and 5) also to the ignition relay...any feed back would be much appreciated

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That's pretty much it - on some models, depending on which you get the harness from, some of the power supplys are already wired to one another, so in practice (mine came from a 90 Loyale) I have the fusible link, and 3 20amp ignition controled circuits for everything else. There is also the light green/white wire that gets power ONLY when cranking.

 

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my set-up is also from a '90 and I understand what you mean by the wires being connected to everything else...could you explain further why the light green/white wire gets ONLY power when cranking...maybe a pin # if not to much trouble...

That's pretty much it - on some models, depending on which you get the harness from, some of the power supplys are already wired to one another, so in practice (mine came from a 90 Loyale) I have the fusible link, and 3 20amp ignition controled circuits for everything else. There is also the light green/white wire that gets power ONLY when cranking.

 

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my set-up is also from a '90 and I understand what you mean by the wires being connected to everything else...could you explain further why the light green/white wire gets ONLY power when cranking

 

It's just an ECU function - I don't profess to know *exactly* what the ECU does with this info, but the idea is surely to notify the ECU the engine is cranking at a low speed and to set the base timing and fuel settings accordingly so the engine will actually catch and start.

 

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most helpful..I promise, just one last question here,..on pg26 and looking at the fuel pump relay connector diagram ..the LW(blue/white)wire #4, does NOT have the letters "IG" power for this wire,..How is this wire to be connected for it 12V power source..Thanks again...

Pin #.... 18.

 

Check out page 32 of the conversion manual, it's all detailed there. The function is present on ALL ignition switches - even my EA81's have it.

 

Oh - and it's light green/yellow - my bad.

 

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Well - you'll notice that terminals 1 and 2 are IG power.... and that's all you need. 1 and 3 are the relay control wires (they close the relay). And terminals 2 and 4 are the fuel pump power supply. When the ECU grounds terminal 3, the relay will close and pass 12v from terminal 2 to 4 and on to the pump.

 

So I guess the answer to your question is that LW (terminal 4) is powered by terminal 2 when the ECU determines it is necesary to run the pump and activates the relay ground.

 

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Now that you tell me this, it seems so obvious, it also tells me that I have been looking at the wireing diagrams a little to long today, anyway it has been a real learning experience in patience to track all the wire pathways to get an understanding of what is really going on, at least from someone who has very little understanding about electrical issues...now off to get the fuel hoses/wire, fuses etc and get this set-up to make it "plug and play"...

Well - you'll notice that terminals 1 and 2 are IG power.... and that's all you need. 1 and 3 are the relay control wires (they close the relay). And terminals 2 and 4 are the fuel pump power supply. When the ECU grounds terminal 3, the relay will close and pass 12v from terminal 2 to 4 and on to the pump.

 

So I guess the answer to your question is that LW (terminal 4) is powered by terminal 2 when the ECU determines it is necesary to run the pump and activates the relay ground.

 

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