3.9 efi no fuel, wont start, tested injectors right bank 8 ohms.........

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cljcars

Active Member

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328

• Mar 14, 2024

• #1

I have 3.9 EFI range rover in a 90. It turns over, sparks, but wont inject fuel. The fuel pump spins. Not checked pressure yet as it seems to move fuel. It just stopped whilst idling a while ago, now won't fuel.

Gone though the Haynes manual efi checks. Everything's good until the injector testing from the ecu end of the loom. Pin2 with pin 11 or 13 resistance check. Left bank 4ohms, right bank is 8ohms suggesting broken wires coils. Would this stop the engine from starting at all? Does the ecu check the resistance then refuse to start? So not putting any fuel in........

 

Last edited: Mar 14, 2024

kermit_rr

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Full Member

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North Shropshire

• Mar 14, 2024

• #2

If your coils are unplugged, it should still inject fuel if the engine isn't immobilised. To my knowledge.

 

Western Slope Rover

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4,073

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On a mesa

• Mar 14, 2024

• #3

Spinning and working are two different things. Pull the fuel line leaving the fuel filter and turn your ignition key to the run position. Fuel should noticeably shoot out of the filter when the key initates the pump.

 

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cljcars

Active Member

Posts

328

• Mar 14, 2024

• #4

OK, I will test the fuel pressure.

It's a 14cux EFI so if the coils disconnected the ecu will not get a signal to inject fuel.

But will it still try and inject fuel if, as tested, 2 off the injectors appear to be out of the circuit?

 

discool

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13,620

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Sector 12 in Kent, The Garden of England

• Mar 14, 2024

• #5

cljcars said:

OK, I will test the fuel pressure.

It's a 14cux EFI so if the coils disconnected the ecu will not get a signal to inject fuel.

But will it still try and inject fuel if, as tested, 2 off the injectors appear to be out of the circuit?

Click to expand...

The EFI ECU needs to know the engine is running, so it receives a signal from the ignition coil, if it doesn’t then the fuel pump won’t continue to run after its initial priming of the fuel system.

What addition of Haynes manual are u using RRC or Disco1 ? as I have both and it maybe possible there’s a slight difference between the two.

 

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cljcars

Active Member

Posts

328

• Mar 15, 2024

• #6

Hi, Yes the fuel pump primes for a second then goes off when the ignition is turned on. I have checked the cable to the coil and this is good. I have the RRC haynes. The discovery wiring diagram looks the same as the one in the Haynes. The colours of the wires all match up too, and the location on the ECU.
Do you know if there are 2 potentially failed injectors. Would the ECU know and not run the fuel pump?

 

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cljcars

Active Member

Posts

328

• Mar 15, 2024

• #7

Well, I found the injector issue. But this has not solved the no start. Which is what I expected to be honest.........

 

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cljcars

Active Member

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328

• Apr 25, 2024

• #8

Well, funny story....... Turns out the previous owner gave the landy to a garage to try and fix after it stopped. They swapped coils distributor and HT leads. Turns out they didn't connect them up correctly. Whoops........ As soon as I sorted the ignition wiring it fired up. The old ecu that the previous owner had replaced was not working. The garage told him to try a new ecu, he did, but they had wired up the coil wrong so it wouldn't run.