I replaced mine this past summer for a similar issue.

There are 3 main things that need to be done.

1. Remove the upper intake manifold to be able to remove all the connections for the fuel injectors

2. May have to remove the drivers side valve cover. There is a 13mm bolt that attaches the wiring harness to the engine block so it is secure. It is difficult to remove this bolt without removing the valve cover.

3. Remove the inside center console and drill out all the rivets holding the cover for the shift lever. You don't have to un-attach the shift lever or transfer case lever. By removing the center console you will have a lot easier time removing the wiring harness where it sits on top of the transmission. It is secured with a couple of zip ties that are almost impossible to get access to without the center console removed. And pulling the old harness out and placing the new one it is dramatically easier with it removed. Basically remove it in about 20 minutes will save you hours dealing with the removing and installing the wiring harness.

Also, look where the harness plugs into the ECU. There will be a white table on it with the part number for the harness. When buying a new one make sure it has the same number as yours. Land Rover made different wiring harnesses.

 

To test the MAF against the O2s, I have take out the upper intake, coils etc, resplice O2 wires, put it all back together, then test them. If they still don’t work, I disassemble again to replace harness.

Or I can just replace the harness and the test when done.

By the way, the wire gauge of the connector pigtail is bigger than the wires coming from the harness. If the harness wire gauge is around 24 (a guess) then the pigtail wires are around 20. The replacement connectors are for a Honda, not Land Rover—the plastic connector is identical but not the wire gauge. Is that a problem?

Thanks again.

 

I've used the Honda connectors that make the wire loom longer with no issue. I notice also the wires were thicker but I had no issues.

Here is what I used.



I'm not sure about the drivers side but if you could un-attach the wires from the Honda connector and use that connector for the Land Rover wires you may be fine. It looks like it is possible for your passenger side. Although access to the wiring harness on the drivers side is much more difficult to do this.

 

The wires on the driver’s side are short—I need the extra wire of the Honda pigtail connector to reach them. Frankly, the hardest part of the job is stripping the insulation off those tiny brittle wires.

 

So I removed the upper intake and left valve cover which makes for easier--but not easy--access to the wire harness.

Three of the 4 wires (brown/pink, white/orange, red/blue) are the same length and long enough to to work with. The orange wire, which goes to the ECM, is bundled with the red/blue wire in a black casing (see photo) that contains the shield wires that block interference. The casing was cut along with the orange wire, exposing the shield wires. When splicing the orange wire, do I need to avoid keep the shield wires outside the splice? Is it a problem that the shield wires/casing have been cut back? Would a shorter shield result in interference that causes bad data to be sent to ECM?

Plan B is replace engine harness. I don't recognize the location shown in the RAVE manual drawing of where the engine harness connects to the main harness. Can anyone identify the location in the vehicle? It does not appear to be on top of the transmission. Where does the engine harness connect to the ECM? Behind the trim panel by the gas pedal?

Thanks again.

 

That drawing looks like it's on the passenger firewall, behind the engine compartment fusebox. However, it may be from a RHD vehicle as the round object on the right looks like a brake booster.
Passenger side firewall makes sense though, as I think that would be close to where the ECM is mounted.

 

The red/black is the ground for the heater, the pink/purple is the power for the heater. Those two are not critical with respect to quality of connection or shielding. The orange and orange/white are the low voltage wires to the ECM, they send a zero to 1 volt analog signal to the ECM, so not too sophisticated. I would not worry too much about the shielding but you should try to keep the shielding wire out of the core wire when splicing.

 

My suggestion is replacing the wiring harness.

You are about half way there by removing the manifold and valve cover.

Just remove the center console and drill out the rivets holding in the gear shift be be able to remove the old harness and place the new harness.

Having a fully intact wiring harness with no repairs is worth the peace of mind vs second guessing the repairs if you still get check engine codes after putting everything back.

 

The engine harness doesn't connect to the main harness, which is why you're having trouble finding it in the RAVE. It's a standalone harness that connects to the different computers in the passenger footwell, as does the main harness.

 

Hey LADisco2,
My 2002 landrover discovery 2 recently got both cats stolen too. I m in the south bay area, Are you in LA. Maybe we can share info. Both of my sensors are not read at all by Smog check people.
Send me private message ( not sure if it is available for free member)
Thanks
Harry