rangerovers.pub
The only place for a coil spring is up Zebedee's arse
Member
Joined:
Posts: 35

Thanks Brian, I hadn't seen they have a similar disclaimer on an exhaust... I guess just protecting themselves.
I'm a big fan of Island, prices are always fair and dispatch times very good.
Yeah, I have a multipoint LPG install on my Thor.

Looks like it is a labeling error on the nanocom itself, as you say after conversion those numbers would be way out!

Thanks for checking your MAF readings. Interesting that yours are at a similar value. I can't say the car runs poorly other than sometimes at idle, only on LPG with the AC on - the revs dip every now and then.
Now the engine has had a refresh, the LPG system is next on my list.
Errors P0175 and P0172 seem to be closely linked to a failing MAF though. I might just buy one just to try it. I'm not sure how long the current MAF has been installed, but there are some numbers on it that could suggest a 2017 build date, so potentially not that old.

Thanks Richard. I guessed at the new thermostat causing it. It's slightly hotter than I'd have preferred, as it's always nice to have a little more tolerance, but I'll just keep an eye on it for now.

Member
Joined:
Posts: 1052

Its probabbly a case that they have had some of those items returned before and had grief off the buyers over them would be my guess. I'd suspect a fully warmed up engine might be closer to what your seeing. I'd have taken it out this evening, but It was throwing it down with rain, and I discovered this weekend that the wiper blades have had it (not that they do that good a job clearing the screen when they are in good condtion anyway). I did try last night but discovered the lost codes on the nano, and by the time I'd put them back in and got round to it was getting a bit late to go out and take it upto 2500rpm!

Its possible either injectors or vapouriser is in need of some TLC - injectors more likely to show problems at idle as thats where the fuelling needs to be more precise anyway. Also a leaky vapouriser might be more noticable at idle. If the same codes don't appear on petrol, then you know its got to be down to the LPG side really.

I've seen the same disclaimer on other bits on Island - that one came up searching for LPG on their site.

Member
Joined:
Posts: 1210

If some vehicles have both a P0175 (bank 2 too rich) code and a P0172 (bank 1 too rich) code then they may also be likely to flag a P0103 (MAF voltage too high) code. The reason for this is that the MAF gives higher signal voltage the higher the airflow and the ECU should provide more fuelling the higher the airflow. Both banks seeming to have too rich mixture (or both bank1 and bank2 lambda sensors being wrong) is a less likely fault (more than one component gone wrong) than a single component fault of an over-reading (in voltage terms) MAF sensor. That would make sense... But you don't have P0103 you have P0102 which points to under-reading MAF... which makes the combination of your 3 error codes curious - An under-reading MAF usually leads to high positive fuel trims (and lean mixture or under-reading lambda sensor codes). The curious part is why would an ECU give error codes for both under-reading MAF voltage (low airflow) and too rich mixture (from lambda sensor readings) at the same time. I.e. Why would it read low airflow but then supply the engine with what it thinks is correct fuelling for high airflow (more air requires more fuel and vice/versa).

Air intake rates / MAF voltage figures can vary by quite a lot for the same engine power (or idle rpm) if mixture varies. These days we normally assume mixture is correct when comparing MAF readings (and it goes without saying that the engine is fully warmed up).... If mixture is a bit rich the engine will usually need less air than usual to average to maintain idle speed, if a bit lean (or especially a lot lean) or a lot rich it will usually need more airflow than usual to maintain idle speed. Idling with correct mixture on LPG the engine may need slightly less air than idling with correct mixture on petrol and the MAF reading can be a bit lower than it would be on petrol, that's because of a few things such as the better atomisation of the fuel and the vapour LPG taking up volume in the inlet manifold that would otherwise be vacuum when vacuum is a factor in pumping losses, both are real efficiency gains in the relevant respects.

Got to wonder if some aspect of resetting adaptions, or (on the other hand) 'false' learned values during time with failing head gaskets contributed to the combination of error codes.

If in doubt about the LPG setup would advise getting it running properly on petrol before seeing what happens when it's run on LPG.

Member
Joined:
Posts: 633

The codes may have been generated at different operational sites.

For instance one set generated at idle and another while cruising or while under accelleration.

It also depends on the complexity of the ECU itself. Some management systems have fairly sophisticated models of the engine within their code, and so they know that for a given operating condition (say 2000rpm, wide open throttle) the MAF readings should be within say a 10 or 20% window, and if they stray outside this, they will generate a code. Other systems are REALLY dumb by comparison and just believe anything certain sensors say.

Member
Joined:
Posts: 1052

ac6 wrote:

Thanks Brian, I hadn't seen they have a similar disclaimer on an exhaust... I guess just protecting themselves.
I'm a big fan of Island, prices are always fair and dispatch times very good.
Yeah, I have a multipoint LPG install on my Thor.

Looks like it is a labeling error on the nanocom itself, as you say after conversion those numbers would be way out!

Thanks for checking your MAF readings. Interesting that yours are at a similar value. I can't say the car runs poorly other than sometimes at idle, only on LPG with the AC on - the revs dip every now and then.
Now the engine has had a refresh, the LPG system is next on my list.
Errors P0175 and P0172 seem to be closely linked to a failing MAF though. I might just buy one just to try it. I'm not sure how long the current MAF has been installed, but there are some numbers on it that could suggest a 2017 build date, so potentially not that old.

Thanks Richard. I guessed at the new thermostat causing it. It's slightly hotter than I'd have preferred, as it's always nice to have a little more tolerance, but I'll just keep an eye on it for now.

Rechecked mine today, and idle once warm is showing 16/17 on Nano, 2500 rpm showing around 67 if thats any help to you. Obviously can vary depending where you are/ambient temp etc but that should give some idea of values.