Same thoughts as Bolt did occur to me but I forgot to mention the potential for a gearbox problem being the underlying problem.

I do think though, like Gilbert, that the problem is probably due to duff lambda sensors. I have seen a lot of P38s with duff lambda sensors usually with the owner and general garages the owner used the services of unaware.

Normally if a 0>1v lambda sensor fails it will output close to 0v, which for a 0>1v sensor implies lean mixture, but the error codes point to rich mixture while the symptoms point to lean mixture. If lambda sensors incorrectly read rich mixture it may have the effect of leaning the mixture off. Given the aforementioned (question to everyone) - What are the chances that someone spliced in 5>0v sensors instead of the 0>1v sensors? I know that in this company I have no need to mention that with the 5>0v sensors a 5v signal; points to lean and a 0v signal points to rich...So if a fitter had mixed up their P38 models and spliced in 5>0v sensors on a model that should use 0>1v sensors there would be constant rich running error codes and the fuel trims might be leaned off leading to reduced engine torque, the engine would still rev but the car would lack power and go up through the gears slowly.

I currently have @Jacckk 's P38 in the yard, the last time I saw this P38 was 10 years ago but he fitted a 4.6 to replace his 4.0 and the LPG fuelling was off after the engine change. Today I got it running much nicer on LPG than on petrol, probably due to some petrol injector issues (only petrol injectiors on 7 and 8 seem to be working great, others probably not working very well).

It would be wasteful (time and money) to replace components that are working OK, so first I would want to run some diagnostics to determine which if any components were broken.... But as said, it is likely changing lambda sensors or MAF would fix the problem.

Have you had any components changed on it recently?
How old are the lambda sensors?
Are they definitely the correct type lamba sensors (connected using he original vehicle lambda sensor connecting plugs) or has someone spliced in generic sensors or sensors from an older P38?

P0172 / P0175 point to system too rich cylinder banks 1 / 2

I'd expect the fault to be due to incorrect spec or failed lambda sensors, or a failed MAF.

P1000 Doesn't normally indicate a fault, ir only means drive cycle(s) haven't been completed so the OBD system hasn't had opportunity to detect certain types of faults. Some vehicles have P1000 every time you start them up, the code goes away if drive cycles are completed without other fault codes occuring.

Is this a P38?

Bolt wrote:

So, for 12 bucks, I have bought 30 (minimum quantity) of the correct size and formulation O rings

Hope you don't mind me going slightly off subject... Noticed a problem with my boat hydraulic trim/tilt system allowing the outdrive/leg to drop when it was supposed to be on full tilt for getting the boat out of the water onto the trailer. I'm rebuilding the engine on it and with the engine out noticed a leak from the joint between a hydraulic pipe and the hydraulic pump. I disconnected the hydraulic line and found a damaged O-ring, this O-ring is apparently only available as part of a complete hydraulic pump refurb kit but I managed to find a replacement sold separately that is supposedly compatible. I'm wondering if the O-ring I bought separately (specifically listed on Ebay as being suitable for the line to pump joint on a Volvo SX / OMC Cobra drive) is really compatible and/or as good as an Oring that would have been supplied as part of the full pump refurb kit. Before I bought this Oring I looked at a specialist Oring manufacturer website https://www.polymax.co.uk/o-rings/ which lists the pros and cons of different types of Oring materials for different applications/fluids/etc but it doesn't seem to say anything about what material is best suited to hydraulic pipe joints for a boat application (it does mention materials for car brake line applications). I know the dimensions of the Oring and bought (from an Ebay seller not from the Polymax manufacturer) one specifically listed as suitable for the exact joint(s) they need to seal but I don't know whether the Ebay Oring is OEM spec, just a cheap random spec Chinese made Oring, etc. There are 4 Orings I'd like to change and to change 2 of them the engine needs to be out for access, the engine is out at the moment so now is the time to change them but I'm not sure whether to trust those I've bought from Ebay.

Impressive mileage, also an impressive trip. I'd love a road trip like that.

Hello and welcome to the forum!

Anything in particular you want advice about

I'm not the best person to ask about Rangerovers but I might be able to help, I'm surprised others haven't seen your message and said hello yet.

Clean the injectors as discussed on LPGforum for sure.

I'd be interested to see if cleaning the reducer will cure the over pressure after solenoids open and before LPG injectors start bleeding pressure... But you might find it easier or prefer to just change the reducer.

If I calibrated the LPGTech system I'll have done it in 'standard mode' (as opposed to 'tech mode'), Standard Mode allows more control than Tech Mode (Tech mode is more for installers who try to get away with fit and forget and not do a proper job of calbration). You can adjust the pressure correction with LPG Tech, click Map, Correction, and find Gas Pressure Correction under the Others tab. Right click on a pressure and you can set a deviation from the standard pressure correction (deviation because your input figures are in addition to the underlying calculated pressure correction figures). The figures I mentioned above are absolute, to get to the absolute figures by entering deviations we have to enter figures of +16% at 1.8 bar and +43% at 2.5 bar, the scale only goes up to 2.5bar. You can also set a minimum injector pulse length in Settings, click on the 3 dots beside Injector Type, change Minimum Gas Injector Time to Manual and set a figure such as 2.3ms.

If you want you could email me your setup file (I'll have a copy but would take time to find it as it'll be on an old hard drive from an old Laptop), I'll modify it and email it back to you. It might help but I doubt it will cure the problems in itself.

It's probably due to a combination of problems...

We've been talking about dirty LPG recently, contains dissolved oil ('heavy ends') which comes out of the LPG during evaporation inside the reducer, flows along with gas vapour to injectors, when cold turns into a sticky tar like substance that can prevent or slow the speed of injectors opening https://lpgforum.co.uk/viewtopic.php?t=19640

The reducer could be another problem. Maybe also due to heavy ends, maybe not... I've known quite a few Antarctic reducers have the problem of slightly sticking open gas inlet which sees pressure rise to 3 bar when there is no gas being drawn off (when the gas inlet port should be closed). The gas inlet port could be sticking open due to heavy ends. Or if you haven't monitored the gas pressure reading before the gas injectors start firing for a while, maybe it's been 3 bar before the injectors for a long time but still switched to gas OK until recently in which case we couldn't attribute all your recent problems just to the high gas pressure (although it would never help).

Don't know what ECU you're using but another problem can be that if you have set a 1.3 bar reference pressure we'd expect the ECU's default (none adjustable on some ECUs) pressure correction to compensate Ginj (gas injector pulse length) by around negative 50% if the pressure reading is 3bar, the default ECU settings are based on physics but don't take into account that the higher pressure will also have the effect of slowing the speed of injectors opening, so at such a high pressure (that will make a big difference to speed of injectors opening) the negative 50% is vastly excessive and has the effect of leaning the mixture due to too short Ginj. If the over-pressure situation is momentary (say the pressure decreases rapidly as soon as injectors start opening) it can be better to dial in a positive (obviously as opposed to negative but I mention it to highlight the point) pressure compensation for pressure readings above the usual range that will be seen during normal engine operation to prevent the over-pressure from leaning the mixture and also to give the injectors a longer pulse to give them better chance of opening and bleeding some of that pressure when they are first pulsed during changeover.. If possible I'd go with the standard pressure corrections up to 1.8 bar, then a zero correction to 2bar, then a positive correction up to around +15% at 3bar. Heh, my +15% correction for +3bar will be around a 65% longer pulse than the ECU would give with standard pressure correction. At cold changeover there'll also be some negative Ginj correction because besides pressure cold gas is denser than hot gas. That said, some ECU's also have a default minimum injector pulse length for the type of injectors you've selected in software (and some others allow a minimum pulse length to be defined by the installer). What ECU are you using?

Could be one I converted, I don't remember whether I did yours or not lol.

Devon Police sent me a couple of pics of myself driving my van with caravan on tow towards Cornwall back in August a few weeks ago, with a 'identify the driver' notice for not wearing a seatbelt. Pics taken from a few different angles, one showing my car and caravan from almost front on, one a down shot through the windscreen. I didn't know they had cameras that flag people not wearing seatbelts.

Kbs wrote:

Many years ago, I was developing OBD systems and I cant think of a link (other than rotten loom) between these errors (gearbox, cranksensor, temp sender).

I'd be interested in a chat about the development of OBD systems but that can wait until another time after your questions on thread have been answered.

My Launch gear seems able to do quite a lot on Land/Rangerovers including suspension stuff, not a cheap option but the Launch will talk to most modules on most vehicles.

If not a collapsed flexi could it be a problem inside the ABS unit?

Gilbertd wrote:

V8 Developments do ported heads in 3 stages (http://www.v8developments.co.uk/headporting.htm) but I'm not aware of any 4 valve or OHC aftermarket ones. While checking out the Wildcat heads, I came across this https://www.ebay.co.uk/itm/115732141242, a pre top hatted block for not that much more than the cost of getting top hats fitted to an existing block. A good mod if building an engine is to use the 4.6 crank and con rods with 4.0 litre pistons. As the 4.0 litre pistons have a smaller dish, that ups the compression ratio to around 10.3:1 (ish). Pre-ignition won't be a problem with the knock sensors to back off the ignition timing if it occurs or if running on LPG with the much higher octane rating.

I remember V8 Developments advertising in car mags I read in the early 90's.

Come to think of it, while there are plenty aftermarket heads (especially Chinese made) for SBC and SBF engines (with various chamber volumes so you can pick your compression ratio) there doesn't seem to be any 4 valve per cylinder OHC heads for them either... Again, given the popularity of the engines would've thought there'd be a few firms making them. I quite fancied some big flow heads for my SBF boat engine, just spent over £120 on one of my cast iron heads but I could've bought 2 new big flow aluminium heads for around £700 and gained around 100bhp... but then to use the boat on saltwater I would've needed to fit a closed cooling system with water to water heat exchanger setup. Strange that there are no 4 valve per cylinder OHC heads for SBC and SBF engines when there was at least one firm making 4 valve per cylinder heads for the 4 cylinder Pinto engine (and iIrc it was an American firm) well before Cosworth made their 4V per cylinder Pinto head... Begs the question why they didn't make 4V per cylinder SBF and SBC heads, would only need to fit a toothed cambelt drive (or 2) between the harmonic balancer and front pulley, remove the tappets and plug the tappet oil feeds.

Just finished the L322 LPG conversion, can't believe how long this one took me I've been working on it all week! when 10 years ago I used to rattle them off in a few days! For sure I've done things a bit differently on this conversion compared to those I did 10 years ago, had to relearn some stuff that I used to be extremely familiar with, in fact so familiar it seems I didn't even bother making notes. All good and running great but I haven't quite finished even now, I still have to refit some boot trim, the engine cover, couple of nuts on the heater air intake panel that goes over the engine and recheck calibration from a cold start in the morning. Checked my records, seems it's been 10 years since I last converted an L322 (the last one I did was a supercharged one, this is the 4.4 normally aspirated engine) but I've fixed the LPG system on a great many L322's and other model Land/Rangerovers during that 10 years and converted around 1000 vehicles since then.

I was expecting to get this L322 converted in 3 days leaving Thursday and Friday to work on my boat engine. I've already got all the short block re-assembled (more or less, still need to fit the brass core plugs), the last thing I did was to re-lap the valves on one of the heads. The next thing I'll be doing is to check the other head and re-lap the valves, then I'll be refitting the tappets and refitting the heads. Can't wait to get it all back together and refitted in the boat so I can try it at least on the river once or twice before winter.

I'm surprised there was never a bigger market for better flowing heads for the RV8. Also given it was in many ways ahead of it's time being an aluminium V8, with a long span of production, and used by sports car manufacturers, it's surprising there were never 4 valve per cylinder overhead cam heads made (which could use external cam belts).

I once bought 2 'grass track' spec RV8's, one with big cam and valves, the other with standard-ish cam but supposedly stronger bottom end, with the intention of fitting one of them in a Ford Sierra. I eventually bought a 'proper' Ford Sapphire (Sierra) Cosworth with the well known 2L Pinto derived but 16valve and turbo'd Cosworth engine but there were a few RV8 powered Sierra's around.

leolito wrote:

Make sure the owner read this and comes for his wheel lol

Hehe! After 10 years I doubt they'll be coming back for it :-)

Recently I got rid of a full car (Merc ML AMG55) that an owner left with me for over 7 years, I've had the wheel here years longer than that.

no10chris wrote:

I have a 19” with good tyre £25, it’s the type with dimples round the edge, don’t ask me to put a picture, I gave up trying that a long time ago 😂🤣

Reminds me...

I have a mint condition standard L322 alloy wheel here, it was the spare wheel on an L322 I converted to LPG years ago, both the wheel and the tyre on it look like new, completely unused, but the tyre will be old so will probably need replacing anyway (or may be OK as is to use just as a spare).

It's been here over 10 years. I don't remember whether it's one I forgot to put back in a car after converting it to LPG or if the owner asked if they could leave it here to come back and collect it later, I do remember the owner phoned me about it a few weeks after I'd converted their car asking me to hold on to it for a bit longer and they'd come and collect it but that was over 10 years ago.

If anyone wants to come and collect it they can have it.

I don't know the dimensions of a P38 petrol tank so can't advise what LPG tank(s) you could replace the petrol tank with if you wanted to run monofuel LPG.

For the old Discovery's it was common practice to remove the original petrol tank, fit a smaller petrol tank and LPG tank in it's place.

The design of the Classic lent itself well to fitting a very unusual design of LPG tank underneath... a trapezoidal design tank. But that design was almost uniquely used on Classics, high cost and unusual to fit even on Classics. As has been said, most Classics had other tank options fitted, mostly cylinder tank in the luggage area or vertical toroidal tank in the spare wheel location.

On a P38 the biggest size tank that will fit flush in the spare wheel well is 720mm x 270mm. Such size tank will be rated at between 84 and 95 litres, the lower figures for 30 degree hollow centred designs, the higher figures for zero degree or 4 hole designs. It is possible to remove the bottom of the spare wheel well to fit a deeper tank (more than 270mm and 720mm wide tanks are made up to 350mm deep) but the P38 design has a rear antiroll bar close to the spare wheel well which cannot be fouled by the fitting of any deeper tank, hence most tanks in P38 spare wheel wells will be 720x270.

On P38's a second tank can be fitted in the luggage area. Such tank can be made removable using (e.g.) hanson fittings. I don't own a P38 but my Elgrand has a 720x270mm 95L 4 hole fitted to the external spare wheel position and a couple of hanson fittings that extend into the rear luggage area - currently I have an 80L cylinder tank hooked up to those hanson fittings and I refuelled with 175 litres of LPG today. When I no longer want the additional cylinder in the boot fitted I will very easily remove it just by disconnecting the 2 hanson fittings. My 720x270 95L 4 hole has working capacity of 95L because I modified it to fill to 100% instead of the usual 80%. My 90L rated cylinder fills to 80L.

When you have the ability to add a 2nd tank inside using quick release gas connectors you're not just limited to adding that single extra tank,. I could add any number of extra tanks and carry them inside, switching tanks as easily as switching between quick release connectors. The permanently fitted 720x270 external tank gives me 300+ mile range, the 80 net litre cylinder gives me around 300 miles on top, I could easily add a 3rd / 4th tank. Just with 2 tanks fitted I can tow my large caravan 500 miles without needing to refuel. I have thought about removing the petrol tank to permanently fit an LPG tank in it's place - which might (combined with just the 720x270) give range on LPg of 600 miles or 900 miles with 1 additional tank.. With that kind of range on LPG you don't need the facility to be able to run on petrol.

Aragorn wrote:

I'm guessing the reluctance to crank was due to water in the cylinder(s)...?

I'd think so, my boat's SBF V8 did the same when it had water in cylinder(s) from a failed marine (water cooled) exhaust manifold... And it had a knock so I did wonder if hydrolock had bent a rod, but as it turned out at least it hadn't bent a rod.

I won't go into much detail about what I've done to the engine so far to fix it but had to modify my engine crane just to lift it out, found scratches in at least one of the cylinders as though the rings were binding, on removing the piston from that cylinder found it was scored / burned and rings had lost springiness. Took ages honing it (especially cylinder 2), put 8 new pistons in (pita pressing old pistons on and heating little ends to fit rods to new pistons). The only part of rebuilding the engine I haven't personally done is skimming the heads, I took them to a machine shop yesterday to be skimmed. They heads might've been OK but had a bit of pitting around the fire ring area and I didn't want to risk it.

Post crossed with Gilbert's

Great if it works but at over £30 a bottle it's a bit of a gamble. Adding additional bottles might sort my V6's problem but it's knowing where to draw the line, I 'bottled out' (heh pun) after trying one bottle. If only we could buy bottled nanobots lol.