3.5 flapper with no life in fuel pump or injectors

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Spuddly7

New Member
Posts
8
Hi,

Range Rover 3.5 wont start.

Does turn over and everything seems to work but wont catch on amd run.

Replaced lots of things Fuel Filter, Plugs, Battery, Fuel pmp relay

I have a couple of manuals and so have been running through the EFI testing in the workshop manual. everything goes to plan until i try and check the resistence of the injectors from what I think is the fuel pump relay they are reported to need to be between 7-10 KOhms all mine are a lot less than that probably more like 8 Ohms. When disconnecting them after the 4th one not sure what number it is I get 1 which is a high resistance. I have some other injectors which I am swapping over and testing.
Separate to that the model of EFI is 4CU which I have heard does not start the fuel pump until the flapper is opened and ignition on??. However I cannot get the pump to run through ignition and starting. I can manually feed pump and it pumps hapilly. I have checked the fuel pressure at the cold start jet and that seems to be about 30 + so don't think there are pump issues providing the pump will run.

Can anyone let me know which is the fuel pump relay. Plus anywhere that I can send my ECU as I think that is might be the cause of the problems.

I have also heard that you can bridge the fuel pump relay to by pass itfor testing i guess but unsure which ports to jump.

any help greatly appreciated!

Spud
 
Not being a mechanic I can only offer advice on one of your questions. The fuel pump relay is the one nearest the trans. tunnel, under the drivers' seat.
 
Hi Thanks very much for that. I was under that impression but a publication I had seen confused the hell out of me.

Anyone know how to bridge the fuel pump relay.

Cheers Ian
 
Hi,

I have been out again trying to get the Range started.

I have discovered that at some point that the fuel pump circuit fuse has blown. Can anyone suggest why this might be happening?

Cheers Ian
 
cos prehaps you are bridging wromg pins?

injectors are low impedence..ie low ohms..not 7-10k..
 
Ahh! Thanks that might be Ok then as they are low 008 Ohms.

I have not bridged the pins on the relay yet as I am trying to get a good output to the Fuel Pump.

I have got a multimeter wired up to fuel pump feed and it appears never to get above about 8V, which to me seems to suggest that the wire from Fuel Pump relay taking too much from the 12V from the feed for the fuel pump to work.

I am looking to run a new cable to the fuel pump from the fuel pump relay. I think the feed wire to the pump is white according to the circuit diagrams. There are at least 4 wires from the fuel pump relay.

White with purple
Black
2 white and another colour.

Has anyone any idea which wire goes to the fuel pump positive connection.

Cheers Ian
 
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