Learning about the 3.9 14CUX ECU

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DaveEFI
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Re: Learning about the 3.9 14CUX ECU

Post by DaveEFI »

Way I went too, Eliot. Although I do know of an SD1 with EDIS/Megajolt and Lucas flapper injection - albeit Mark Adams modified, since it's got a 4.6 RV8. There probably is someone out there who has done the same with the hotwire.


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garrycol
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Re: Learning about the 3.9 14CUX ECU

Post by garrycol »

Eliot - thanks for the interesting information but not going MS at this stage - hence the 14CUX questions.

Cheers

Garry

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ChrisJC
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Re: Learning about the 3.9 14CUX ECU

Post by ChrisJC »

For Range Rovers of the vintage that used the 14CUX, they used a short cable coming from the gearbox into a separate transducer.
The transducer is part no. AMR3386 and the cable is PRC7979, all available from Island 4x4.
The sensor has just two wires, I think it is a reed switch, so it needs some circuitry to drive it.
If you were to find the wiring information for said Range Rover, you might well find that the signal is adapted in some way to drive the ECU.
I have just measured one, and it goes between about 120ohms and open circuit 8 times per revolution of the speedo cable.

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GDCobra
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Re: Learning about the 3.9 14CUX ECU

Post by GDCobra »

garrycol wrote:
Tue Apr 23, 2019 11:30 pm
Back to speed input to the 14CUX (Hotwire) ECU.

I am looking at this to provide speed input to a 14CUX (Hotwire) ECU in my FC101. A friend also has a FC101 with 14CUX system and he does not have any speed input to his ECU and the vehicle runs and idles fine.

So is speed input important to the 14CUX Hotwire ECU?

Thanks

Garry
I guess there is no reason this would be a problem as long as the idle is high enough. I think the reason for this is to make gear changes a little easier. However when I didn't have mine hooked up the engine would stall now and again when coming to a stop. Could have just been my engine though.

garrycol
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Re: Learning about the 3.9 14CUX ECU

Post by garrycol »

Thanks to Chris and GD for that input - I will have look.

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