Gunk is horrible smelly stuff. Do you have Screwfix in ROI? They do some stuff called No Nonsense Degreaser. You can brush it on or if you have the bottle that fits on your pressure washer use that to spray it on, leave it for a couple of minutes and blast it off. Works superbly.

The only part shown on LRCat that looks similar is ANR2985, available just about everywhere but your, or at least the remains of yours, looks slightly different. To avoid problems with duty and VAT, they are available from LR so your local main dealer can supply, or try RLD Autos in France (www.rld-autos.com).

Yes, there's clips at the bonnet hinges.

Probably no more than my Launch C Reader, OBD engine functions and that is all, none of the other systems. Biggest problem with the P38 is that it is pre-Canbus and most systems use proprietary, non-standard protocols, hence needing a dedicated tool. My Nanocom has licences for GEMS and EDC (diesel) but not for Thor, so if I need to check the engine on a Thor I use the C Reader for that (which also works on every other car I have ever tried it on, including Jap imports with JOBD).

Seems a bit odd. I had ABS Fault and Traction Failure come up on the Ascot but that was down to one dead wheel sender. For traction Failure to come up when you are doing a bit of low speed shunting seems very strange, particularly as the traction control wasn't even trying to kick in, that only happens if one wheel is losing traction.

There might be a stored fault with it that the Nano can read though which should give you a pointer to where you need to be looking.

Told you I know nothing about the diesel......

In your last picture, the radiator mounting is the same as the V8, the top two lugs and the pegs at the bottom (and the two bolts that achieve nothing) and will just lift out but by then you've already got the fan and cowling off. From your pictures I can't even see where the water pump goes! As for the pipe, not a clue.....

Screw a suitable size nut onto a bolt, screw the bolt into the Rivnut and put it into the hole, then, holding the bolt so it doesn't turn, screw the nut clockwise so it is against the Rvinut and keep tightening it. That will pull the Rivnut into place so you will then be able to unscrew the bolt and attach your side steps. If you want to get really flash, you could even put a washer between the nut and the Rivnut.

Not being familiar with the diesel at all, I just checked RAVE and the first thing it says to do is remove the radiator assembly. Looking at the parts catalogue, it looks to be the same as the V8 where you can lift the radiator out leaving the cowl in place. With it all slack you lift the cowling slightly so the pegs clear the holes and move it back so the radiator can be lifted out. Once that is out, the cowling can be moved forwards, away from the fan, and lifted out too. There shouldn't be any need to remove the power steering reservoir or washer filler neck as they are attached to the frame that the radiator sits between (unless it is completely different to a diesel but I don't think so) which all stays in the car. The one advantage when doing the same job on the V8 is the top part of the cowl clips on so that can be unclipped and the viscous removed with it all still in place. A water pump can be replaced with the engine and cowling still in place.

He can but it won't cool very well, it needs to water to conduct the heat.

My mate did exactly the same with his Classic only his drain was much higher. He'd had the radio out to sort out an intermittent connection and the soft dash Classic has a button on the dash just below the radio to switch the interior lights on and he'd pushed it in while putting the radio back in its slot. As the car was outside in the sunshine, he hadn't noticed that they were on, or at the times he had noticed, he had a door open anyway.

That's right, if you remember when you first got it, you put in two codes, one for the engine type and one for the other P38 systems. When you go to the first screen you tell it what engine licence you have and that affects what options are shown. For example, if you have a Thor licence, it will only give you Wabco D as the option for ABS, a GEMS will only give you Wabco C but if you have the EDC diesel licence, it will give you both as you may be looking at an early car or a later one. There's different options for SRS too as that changed with year and market.

Depends what you buy, some will be marked as Coolant, and is already 50/50 water, others, usually only slightly more expensive, will be marked as Concentrate which you add your own water to. You just need to read the label carefully to see what you are getting.

I said it would be a light bulb......

BeCM will draw around an Amp (maybe a little higher on an early car) so it does look like it is sleeping. Quiescent draw when everything is off should be between 0.025 and 0.04A so you've definitely got something that is staying on. 0.35A would equate to around 4W on top of the normal draw, so do you have a light bulb (boot light, glovebox light, etc) that is permanently powered and staying on for some reason? The permanently powered interior lights are fed from fuse 15 so I would start by pulling that and seeing if the draw drops. Don't forget that clamp on meters aren't that accurate at very low current draw (or mine isn't anyway), so confirming with a conventional meter in the battery lead might be a good idea too.

As you have by now surmised, you have no flow through the radiator, so that is either water pump or thermostat. Not sure about the P38 one but modern thermostats tend to fail open rather than closed. As you say, the viscous only really does anything if you are in traffic and there is no airflow through the radiator, moving at 50 mph you hardly need the fan even.

Not long after I'd found the problem my neighbour wandered round to see how I was getting on so I showed him what I'd found. As he said, if I hadn't been able to find it myself, where would I go? Ashcrofts are the transmission experts but they rebuild gearboxes so won't get involved in the electronic side of things. He admitted that had it been taken into the LR approved Indy he had recently retired from, none of the technicians there would have known where to start and neither would an auto electrician. But, I suppose it was a case of I broke it so I had to fix it......

Definitely an I've started so I'll finish job and I'm happy to report that I've finally cracked it. Figured that it had to be a wiring problem and had found a new looking cut in the outer sheath under the car so rather than try to investigate it laying on my back underneath, decided to take the centre console out. Far easier said than done and the connectors for the loom are under the sound deadening, which is under the carpet under the centre console. Finally managed to get to them and they appeared fine so poked the loom out through the floor so it dangled under the car. Disconnected it from the transfer case so was able to pull the back of the loom out from under the car and at least see it in daylight. Pulled the sheathing back and found one wire had been damaged, the insulation was cut but the conductor was fine. Insulated that and put it all back. On the offchance I had disturbed something, tried the car and still had the Gearbox Fault.

Working forward, I unplugged and checked all the connections to the gearbox itself, nothing wrong there either. All that left was the horrible 6 way Supaseal connector that hangs down behind the LH cylinder head (the one that always gets in the way when trying to take the LH cylinder head off). That looked fine from both above and underneath but decided to unplug it to have a better look. Figured it would probably be easier to unplug it from underneath, got hold of it and as soon as I moved it, this happened.......

Two wires just fell out. Now I may have caught it with the bracket on the gearbox dipstick tube when I'd taken that out or it may be that they were broken anyway and moving the loom while changing the gearbox had allowed the wires to move out enough that they were no longer making contact with the terminal I have no idea. All I know is that the wires all appeared connected and pushed into the plug when I initially looked at it but they came out as soon as I touched it. Unplugged it, dropped it down so it was hanging under the car, found a suitable piece of stranded multicore cable and soldered that to the wires after cutting the plug off. Passed the cable up the bulkhead, snipped the wires from the socket and soldered them too. Each joint was insulated with glue lined heat shrink, then all taped up at both ends too. Started the car and everything was fine, no more Gearbox Fault, all I had to do then was reassemble the centre console. Maybe I should have started at the front.....

Anyway, I can report that the car now drives perfectly. Gearchanges are so smooth they can't be felt or heard, all you can hear is the revs changing. So while it may have taken 3 days longer than originally expected, it's finally done. It's definitely one to bear in mind when that plug has to be disconnected when a cylinder head is removed. No point doing the head gaskets only to find you end up with a gearbox fault instead.

Persistence doesn't have anything to do with it, I need it back on the road and usable. Particularly as it now looks like I caused the problem so I need to fix it.....

Probably not but it gets curiouser and curiouser. Spoke to Dave this morning and he has never had to change a gearbox ECU when swapping a 4HP22 on a 4.0 litre with a 4HP24 from a 4.6 and has done it at least 30 times on different cars, both GEMS and Thor, with no problems. This makes perfect sense as the only thing that is different is the gearbox and while it has an electrical connection, there's no electronics in the box itself, just the solenoids and output shaft speed sensor which are the same no matter what gearbox is fitted. After telling him what I'd found, took a run over to him. Running it with the gearbox ECU from the Ascot in there and the Nanocom plugged in displaying the gearbox inputs, it ran and shifted perfectly. Change points are a touch higher than with the old box but I always thought it changed up a bit too soon anyway (and at lower revs than the Ascot too). We tried all 3 variants of GEMS 4.6 gearbox controllers and all act exactly the same. He was as puzzled as I am.

Connected my graphical meter to display the torque waveform from the engine ECU. It is supposed to output a 12V PWM signal that will vary with engine speed and load. With the ignition switched on but the engine not running, it shows a near perfect square wave of around 8V peak and wide ON pulses. At that point the Nano shows an engine power of around 15 (not bad for an engine that isn't even turning over!). Start the engine and the pulse widths reduce slightly and the Nano shows a power reading of 50 ish, rising with revs. After around 20 seconds of running the pulses change completely to a very narrow pulse but at a level of only 0.7V. It is when this change happens that the power reading on the Nano changes to 236. Tried it without the Nano connected and the pulses changed just the same but as soon as they do, Gearbox Fault pops up and the gear display goes out. So, we now know what is causing it but not why and both agree that it is an electrical fault rather than anything wrong with the gearbox itself. A swift Google for P38 Engine Torque Fail, came up with this thread which describes that exact same symptoms I have https://www.rangerovers.net/threads/nanocom-engine-torque-fault-on-1995-auto-4-6-gearbox.334994/. That seemed to suggest a misfire, which I don't have, would cause the torque figure to drop and trigger the fault although I don't have a torque figure that drops, I have one that rises? In theory that should simply make the gearbox ECU think I had booted it. Although the writer of that thread didn't check and see the disappearing pulses from the engine ECU though.

Having got back home, with a spare gearbox ECU identical to the one from the Ascot, which Dave gave me. I wondered if I had some sort of incompatibility between my plod spec engine ECU and the 4.6 gearbox ECU. So, with the Ascot gearbox ECU in the car I pulled the Ascot engine ECU out of it too. Using the Nano Security Learn feature, paired it with my BeCM. Monitored the Torque pulses from it and the same. Perfect PWM signal with ignition on, start the engine and after 20 seconds the pulses disappear. While the Ascot engine and gearbox ECU's work fine in the Ascot, they don't in mine. Tried my engine ECU in the Ascot and the pulses don't disappear and it behaves perfectly. Swapped everything back so the Ascot was back to as it was and my car was but with another gearbox ECU identical to the one from the Ascot. Time for a coffee.....

While drinking my coffee I had another read through the thread. It isn't until post #15 where the actual cause of the fault is found. A dodgy connection in one of the wires between engine ECU, gearbox and gearbox ECU. Then it started to become clearer. This wiring exits the car under the centre console and dangles down underneath before going to the gearbox and transfer case. As it had been shoved around quite a lot while the two big mechanical bits had been removed and refitted, it may well be that one of the wires has been damaged. I've had a quick look underneath and found a new looking cut in the outer sheath but opening it up and the wiring all appears fine. It's quite possible that the movement has either broken a wire or caused a bad connection in one the the plugs under the centre console. So at the moment the console is partway out and I'll continue in the morning......

KCR wrote:

Hi Richard, sorry for Your gearbox :-( please give an update if the hp24 fits, as I am planning the same swap (the one from a 4.6 GEMS with a bigger torque converter). If it is plug & play (I guess the tranny ECU has to be swapped, too?) but if they are the same lengths and how the 4.0 feels with the bigger TC? Would be gr8!!!

The 4HP24 fits and is a direct swap as long as the spacer behind the flex plate is changed for the thinner one from the 4.6 so the flex plate is closer to the flywheel giving more space for the larger torque converter. Seeing them side by side, it is quite a bit larger too so I thought it might affect the feel of the engine as it is in effect giving it a heavier flywheel but it doesn't seem to, it seems to feel no different.

As noted above, it does appear that I need to change the ECU but whether that always applies or is unique to my car because it was built to police spec I've no idea. My old 4HP22 always seemed to change up sooner than I would have expected it to, and sooner than the 4HP24 in the Ascot too. That and the fact I'm seeing different waveforms between the two cars from the engine ECU would also suggest something odd.