D2 V8 fault codes

[Caveman]

Reposted from the technical chatter forum.

Just wondering if anyone can shed a bit of light on a fault code report I received for my Disco II.

I took the car in for a mechanical check, and was presented with the following list of faults that they had pulled from the computer.

From the report:

ENGINE: OXYGEN SENSOR HEATER BANK 1 & 2
LAMBDA SENSOR UPSTREAM OF CAT BANK 1. MONITOR OXYGEN
SENSOR CYCLING. LEFT SENSOR FOUND NOT TO BE CYCLING. ACE
MAIN RELAY TEST FAILED.

Can anyone explain what that means in laymans terms, as I'm not clear, and the mechanic didn't really seem to be able to explain it either.
I just want to know what the faults are, and what I need to do to fix them.

Any help would be greatly appreciated.

Cheers
Paul

[Scouse]

I'm sure the oxygen sensor faults are 'ghost' faults as your car doesn't have these fitted.

Did you have any warning lights displayed or were these faults stored in the ECU ?

[Caveman]

No, I've not had any warning lights on the dash.

I've only had the car a couple of weeks though.

[Scouse]

In that case the only fault that is of some concern is the ACE relay.

However, if the ACE warning light isn't displayed then I wouldn't be too worried. It might have logged a fault from low voltage at one time or something else as simple as that.

[Caveman]

I'm sure the oxygen sensor faults are 'ghost' faults as your car doesn't have these fitted.

Did you have any warning lights displayed or were these faults stored in the ECU ?

I've just been under the car and it definately has a sensor on each exhaust just before the cats.

Anyone able to shed some light as to the problem.???

[LandyAndy]

Caveman
Bare with Scouse,he fixes them for a living,1 or 3 others here that also throw the spanners on Landys for their crust.Im sure the brains trust will sort it for you!!!
Andrew

[Caveman]

No worries mate.

I wasn't implying that Scouse was wrong, just that from what I can see there are 2 sensors on the exhaust.
Of course they may not be oxygen sensors, but like you say, I'm sure someone will be able to enlighten me.

That's why I'm on the website.......to learn from others who know more about LR's than me....which is probably most of you.

All help is appreciated, and I'm happy to pass on any knowledge I have to others as well.

[Scouse]

Sorry to give you a bum steer Caveman. Unfortunately (or fortunately ) I don't fix them for a living now. I'm at a LR dealership but I keep my hands clean nowadays. I know the D1 didn't have the sensors.

I've had a look through the error codes listed with LR & I can't see that specific fault description. Do you know if it brought up an error code (P0101 just as an example)?

Personally, if the car is running OK & there's no warning lights displayed, I would just get the faults cleared for the time being. Anything in the cars' past could have triggered the faults & you might spend $$ tracing something that doesn't really exist.
Keep an eye on things & maybe get the system checked in a few weeks & see if anything similar has returned.

[Caveman]

Sounds like good advice to me Scott.

I didn't get the actual error codes from the mechanic, just those descriptions I posted earlier.

I agree, there are no warning lights, and the Engine and ACE seem to be fine, so I'll just keep an eye oput for any problems.

I have a few other issues to fix, which I'll do first, then check with the error codes again.

Do you think it's worth getting a OBDII scanner to at least be able to read the codes from the car....or a is trip to a mechanic a couple of times a year enough.
I happy to do as much work on the car as I can, before I have to resort to paying a mechanic to do it.

[justinc]

Paul,

I agree with Scott, and also confirm that your D2 does get O2 sensors, as the Thor engines all did. Some other export models even got downstream of the Cat sensors, to tell you the cat was faulty!
ANYHOW, I get phantom codes etc with these all the time, the most interesting red herring was an airflow meter failure on a D2 V8 that told me that all 8 cylinders had a missfire, a 'catalyst damaging' one at that!
The A/F meter code never appeared, the vehicle was just gutless and running hot. ( It DID show way too low Kg/Hr air mass readings for given RPM ranges though)
It goes to show that blindly following instructions from ECU's and their diagnostic counterparts isn't advisable. Knowing the system and how the codes could appear is very important.

JC