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Eunos Roadster jap import. Registered as an 1998
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Discussion Starter · #45 ·
Here's how they show the injector loom plug X-03, if it helps at all. I added colour spots for the ones I think I can read; all but the 3-coloured wire which is black/????/green.

View attachment 61171
I’ve checked the 6 pin plug for 12v on the yellow/black wire and the yellow wire. I do get some voltage of about 9v but it decreases as I keep the voltmeter on it. Any ideas???
 

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I’ve checked the 6 pin plug for 12v on the yellow/black wire and the yellow wire. I do get some voltage of about 9v but it decreases as I keep the voltmeter on it. Any ideas???
That might be okay. Those are the two wires going back to the ECU to control the two pairs of injectors. I'd expect them to be high resistance normally, and maybe float up to some number of volts, and only drop low at the moment the ECU tries to fire the injectors.

Do you see 12V arriving on that plug on the white/red wire?
 

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Eunos Roadster jap import. Registered as an 1998
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Discussion Starter · #47 ·
That might be okay. Those are the two wires going back to the ECU to control the two pairs of injectors. I'd expect them to be high resistance normally, and maybe float up to some number of volts, and only drop low at the moment the ECU tries to fire the injectors.

Do you see 12V arriving on that plug on the white/red wire?
Well when I put my multi meter on the white/red wire and earth I do have 12v on that plug.
 

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Eunos Roadster jap import. Registered as an 1998
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Discussion Starter · #48 ·
Another point I want to make is that when I turn the ignition on my fuel pump relay under the dash makes a high pitch whine for about 5-10seconds and can’t understand why it does this. Any ideas on this.
 

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Another point I want to make is that when I turn the ignition on my fuel pump relay under the dash makes a high pitch whine for about 5-10seconds and can’t understand why it does this. Any ideas on this.
never heard of a relay whining before

working through what a relay does logically, its a metal arm that actuates on and off by a given signal.

I can only think of capacitors whining when they get bad or when electricity whines at a really high current, neither of which apply here as far as I know

Wonder if its worth trying another relay to rule it out.
 

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Eunos Roadster jap import. Registered as an 1998
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Discussion Starter · #50 ·
never heard of a relay whining before

working through what a relay does logically, its a metal arm that actuates on and off by a given signal.

I can only think of capacitors whining when they get bad or when electricity whines at a really high current, neither of which apply here as far as I know

Wonder if its worth trying another relay to rule it out.
I’ll get another relay and try that and see what happens
 

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Discussion Starter · #51 ·
But I’m also beginning to wonder whether it has an immobiliser on it somewhere because under the dashboard there’s a 15amp fuse on its own which looks like it’s been added it. I’ll take some pictures when I get home and see if I can do a video of the whining noise.
 

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Discussion Starter · #57 ·
Sounds like perhaps it was fitted with an after market remote lock at some point maybe

I can feel another post coming "How do I remove the dashboard" :)
🤣🤣 I’ll have a look in the drivers door at the weekend but I’ll deffo take some pictures tonight so you guys can see what I mean. Everything else is working perfectly on the car apart from it not getting 12v at the injectors which it had before
 

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Well, if I understand correctly, the 12V is arriving on the white/red wire at the 6-pin connector which feeds the injector loom, but doesn't get the short distance further to the white/red pins on the injector plugs. If so, that sounds like a break in the injector loom itself.
 
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