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Discussion Starter #1
Im going to shoot for the stars right off the bat, and ask if anyone has a wiring diagram (that a novice can understand) of the harness from a 3.9 V8, which will tell me what every plug and wire is for. I have searched everywhere online that I can think of, and all I have found are diagrams that dont match what I have in front of me, or diagrams that are not detailed enough. The engine/wiring harness came from an RRC, and there are multiple plugs and wires on it that I cant figure out. I also need to know where the harness/ECU gets power, and which wires connect to the ignition coil. I have fuel supplied to the injectors, and the engine turns over, but I have no spark.

I am completely stumped, and I am sure its because I am a rookie, so do me a huge favor and go ahead and treat me like I dont know anything, rather than assume Ive tried what you might consider to be obvious solutions. My level of frustration has reached epic levels, so I am throwing myself at the mercy of this forum for any and all help. :icon_peace:

I am sure I have left out some details that some of you might need to evaluate my problem, so dont hesitate to ask.

TIA,
Kent
 

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A LOT of stuff you will not need mate...the engine came out of a classic RR...it had electric seats, ride height adjustors, bunch of ECU stuff, A/C, etc etc - that you are not going to need. - why don't you just run the basics - coil, ignition, dizzy, battery, alternator and see what that gives you...should be able to get a spark at the spark plug?
 

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Discussion Starter #3
All I'm trying to do is run those basics, but it doesn't seem to be working out.
 

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Is your distributor in the correct location? Being a tooth or two out will cause the same symptoms, wanting to fire but just won't. Unless you are 100% sure that you aren't getting spark.
 

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Discussion Starter #5
Is your distributor in the correct location? Being a tooth or two out will cause the same symptoms, wanting to fire but just won't. Unless you are 100% sure that you aren't getting spark.
The ignition coil is not getting power. That white wire with black rings has no current. That's why I need to know how the harness gets power. Sorry if that seems like an amateur question, but I'm going off a knowledge of EFI engines that is elementary at best.
 

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The attached Land Rover's overview of the 13/14CU and 14CUX and related engine electronic gizmos should get you close, if not all the way there.
What year is the harness from? I have the RRC 14_CUX fuel injection and related wiring schematics for 88', 89', 93', etc. These files are to big to upload, but I could email. LMK
 

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If spark is the problem, I'm confused about the problem. The ignition system has nothing to do with the EFI ECU. The ignition system is a couple of wires. You have power at the coil and to the correct side? the EFI system does not supply power to the coil. It just has a sense wire.
 

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Power to the coil should be straight from the correct connector at the ignition switch. If switching from a diesel, you need to add this wire.
 

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Discussion Starter #9
Where does the coil get its power? I was under the impression that the harness controlled that.... This is what I meant by being EFI illiterate.

Edit: switching from a 2.8 petrol.
 

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Where does the coil get its power? I was under the impression that the harness controlled that.... This is what I meant by being EFI illiterate.

Edit: switching from a 2.8 petrol.
No. Coil power will be the same at the previous engine. The EFI only senses the spark in order to know engine speed and when to turn on the fuel.
 

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Discussion Starter #12
Power to the coil should be straight from the correct connector at the ignition switch. If switching from a diesel, you need to add this wire.
So is it just a 12v switched power wire that I can connect to the + on the coil?

I tried that, with no luck.
 

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So is it just a 12v switched power wire that I can connect to the + on the coil?

I tried that, with no luck.
You need the correct lead from the ignition switch. Most switched power turns off while cranking. The one lead is specifically for the coil and stays live while cranking. The EFI must have the sense wire with resistor as shown or it won't turn on the fuel.
 

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Discussion Starter #15
Thanks, guys. Ill have a look through this stuff and see what I can make of it. Ill let you know.
 

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Pretty sure the power wire to the cool should be brown. Trace that wire back and see what's up with it.
 
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