Gilbertd wrote:
Not a problem she thought as we have charging points for some of the specialist vehicles with auxiliary batteries to keep them topped up when not being used so she figured she could plug her car in there during the day. First time she did it someone queried it and that caused all sorts of discussions. Upshot is that she has been told that under no circumstances can she plug in to charge it during the day. The argument being that nobody else gets their fuel costs for commuting to work and back reimbursed so why should she?
I'm definitely not pro electric vehicles but couldn't the firm just charge her a quid a day?
Orangebean wrote:
The joys of working in the public sector- true equality gone slightly mad. I used to work for a government agency and their rabid adherence to "benefits" rules, on-site employee car parking as a benefit and thus declarable, and their opinion that if they provided charging points for some employees they'd have to provide fuel pumps for the others (Union would have got cross otherwise), meant that even though they'd considered charging points as part of their environmental responsibility, they couldn't.
And ensure common sense prevails?
Different point - If I were forced to go full electric next month I'd make sure I had unlimited range anyway (in a fashion).. I fixed my mates 5kw genny ages ago and he hasn't collected it yet. I'd carry that in the boot with suitable exhaust system etc, probably hard wire it. See where this is going already - Go on to upgrade to a much bigger genny, bigger electric motors for the car, convert the genny to LPG, don't worry too much about the battery aspect. Unless illegal, in which case it might be a stealth install, maybe not hard-wired / hard plumbed... There might be cause to shut-off the genny before stopping for a blue light, much like some people put on their seat belt before an officer appears alongside ;-)
Simon
rickrwg wrote:
Thanks for that Simon my car isn't actually a Range Rover it is a "cough cough" 2003 Jeep V8 HO do you know if this would work with the OBD interface I would like to monitor fuel trims from the laptop as I am getting a flat spot in the mid rev range and am sure its going lean not just on gas but petrol also just more pronounced on gas if you could tell me the pin numbers it would be great so I can have a look what's happening.
I used to have pinout notes on my laptop but that was on the old laptop which broke... getting to know them again will involve either my scouring around in the garage to look for a bit of paper sent by a supplier years ago, or making my own pinout diagram from looking at a loom I have here, but I'm a bit busy to do either at the moment and will be on holiday soon as long as I get all my jobs done!
I'll come back with pinout at some point but it might not be for a while. Still, you'd be better off using an OBD2 live data scanner than connecting the OBD wires of the LPG ECU - The sample rate of the LPG ECU is a bit slow for purpose of using as a calibration aid / If you were to use the connection for purpose for which it was designed (enabling the adaption facility) it still wouldn't make up for incorrect map shape but could cause problems at other engine loads/rpm / Don't know the year, board suffix or firmware of your ECU but it might not support the OBD connection anyway. There was only a period of maybe a year where ECU's that could support OBD connection were supplied with looms that didn't have OBD wiring already connected / On some vehicles, leaving LPG ECU OBD wiring connected can inadvertently interfere with the canbus, which can cause problems ranging from minor such as inability to connect with an OBD2 scanner to far stranger and more concerning symptoms affecting anything on the canbus, even inability to crank the engine on some Mercs. Do yourself a favour and buy a cheap OBD2 live data scanner rather than wire in the LPG system's OBD connection!
Simon
Above advice is sound, I was tempted not to add anything in case it added to confusion but I think this worth saying...
As someone wrote above, if you saved your config before changing anything you could just load the saved config file and all should be well. There can be exceptions to this, though... E.g. Could have a situation where fixing a long term issue highlights other problems - Suppose the engine was running open loop due to problem code(s) due to (say) failed lambda probes. In open loop fuel trims are not applied, so if LPG calibration was wrong the engine could have been running 20% lean on petrol and 20% rich on LPG. The engine might run OKish running 20% lean on petrol or running 20% rich on LPG, in which case switching between fuels wouldn't reveal any further drive-ability problems. But, if you fix the probes and closed loop running resumes, then you run on petrol, the fuel trim needed to correct the 20% lean running on petrol is learned/applied so now the engine runs great on petrol. But then if you switched to LPG the engine would at first get a 40% rich mixture giving poor drive-ability, but eventually the incorrect LPG calibration might steer fuel trims back to -20% and now the engine might run great on LPG, but if you then switch back to petrol it will be 40% lean. I know this reads an unlikely set of circumstances, after all we would expect the LPG system to have been calibrated correctly in the first place and fuel trims on petrol not to be so extreme, but I've seen similar sets of circumstances so often this type of scenario seemed worth a mention. Other issues can be revealed after fixing an underlying issue too, such as worn LPG injectors giving some cylinders a far greater dose of LPG than others. What should be drawn from this is that when you get it running properly on petrol, make sure you check LPG calibration as soon as you run on LPG.
If you didn't save your config file but you only changed reference pressure, changing reference pressure back to what it was should do the same. If however you changed one of a few other things such as type of injectors fitted, that might have changed the map back to the default map figures for the last type of injectors you selected
Simon.
This must be a thread I didn't use topic tracker on... Late to reply again sorry.
It''s been a long time since I had to think about which pins are for the OBD connection (back when OBD connection was first introduced the loom didn't carry OBD wires but you got the OBD loom separate with pins already attached to push straight into the connector block). I could check on the pinout but there probably isn't much point - For various reasons good installers generally think it a bad idea to connect the LPG ECU to the vehicle OBD anyway. Never tried it on a P38 but results of doing so on a P38 could turn out to be very much negative unless it's a very late model. Earlier models are not fully OBD2 compatible and although code readers will connect and read live data, the fuel trim info they display might be have long term fuel trims showing at constant -100% or similar. The LPG system would read the same info and interpret it the same way as a generic OBD2 scanner so the LPG system would also read -100% fuel trims, the result of which would see the LPG system subtracting it's maximum range of -20% fuelling from what might otherwise by perfect fuelling.
Onto another question, there are various AEB boards, some look entirely different and contain different sets of components to others. AEB ECU's have been wearing Romano badges for years but King is relatively a newcomer. If the Romano system is an older board it is unlikely that firmware between it and a King ECU would be compatible given the different hardware sets. If the boards are the same year and same spec then if software allowed you to connect to any system it might be more easily possible to change firmware to whichever brand you liked but software doesn't allow that, so although it would be possible it would involve a bit of hacking...and probably not worth the effort when an 8 cylinder AEB ECU these days is about £150... Years ago the same brand ECU only of course of older spec (not truly sequential like modern AEB ECU's and lacking some of the other features too) would have cost over £500!
Other post - Yeah you could make your own single point controller but, like above, would it be worth it (unless you'd be doing it for fun!) when a controller itself is about £50. The AEB175's such as Leonardo's aren't that badly thought out and cover all of rpm detection, stepper motor driving, relay control of solenoids and lambda connection, ability to limit range of stepper motor movement, adjust speed of change of stepper position for rpm, AD converters to read TPS, lambda and much less commonly reducer temp, DA converter for programmable simulation of lambda voltage, serial link to in-cab AEB fuel changeover switch, etc. Not many guts in them but they do a lot for the money and to fully replicate the functionality yourself you'd need to not only make it but program it and maybe write another program for the laptop to adjust it's settings. There are even cheaper controllers (Bingo is one) that have all the basic functionality without the ability to set range of stepper movement or stepper position during over-run, or in fact any sort of connection with a laptop. I've never had problem connecting to an AEB175 using any version of Windows, I have seen some 175's in incorrect branded cases though, e.g. had to connect to a Millenium using Leonado software lol..
Simon
Orangebean wrote:
super4 wrote:
But here is a question for you- if that vacuum lead is broken does it affect the running ? It has been broken for much of the cars life and running problems have only recently happened
No- cruise control has its own vacuum pump and is completely self contained. Won't affect running in the slightest..
Got me scratching my head now! I have no P38 here to check on at the moment but I was under the impression cruise control on them was plumbed to manifold vacuum? Sure I've heard and corrected vacuum hissing from broken cruise control vac pipe at the firewall end of passenger side engine bay in the past, correcting cruise control function in some cases, and the other end of that pipe went to the manifold..
Orangebean wrote:
Simon- if I can just jump into super's thread and ask a quick question re the 2 banks thing?
You say:
"On an older system setting 2 cylinder banks can affect a bit more than just allowing the twiddle factor for bank 2"
What else can it affect?
I've just replumbed the LP side on mine (Zavoli Zeta S, AEB2856C, Matrix injectors) to achieve an equal pipe run to each of my Matrix injectors- previously had 1 pipe at 600mm long and 1 at 300mm long from the splitter.
Pinj numbers are now out of balance, as you'd expect, so need to rebalance, but what else will be affected?
Ta
Now back to super!
Early AEB systems are not truly sequential, they base fuelling for all LPG injectors on only the blue petrol injector wires (normally front cylinder / same channel as gas injector A and E for banks 1 and 2). Really early systems didn't even have bank trim facility. Later AEB systems are truly sequential (just about anyway!). Some not truly sequential systems can still see firing order, earlier ones can't. Where they can't see firing order firing order is presumed but changing number of banks can change presumed firing order... But since gas injector ABCD still equate to petrol cut wires blu red grn yel, if teh system supports sequential cylinder changeover (which isn't the same as the system being truly sequential) even if gas injector firing order is changed it might still switch between fuels without engine hesitation.
Customer here now, I'll recheck I've replied properly later!
You definitely need to get it running right on petrol before you do anything with the LPG.
If the lambda wires are connected (and they by no means have to be connected) the readings should fluctuate regardless of what fuel you're running on if the engine is running as it should.
This line doesn't over-ride 'running right on petrol first' - I didn't realise you'd adjusted any settings yet. If it previously ran OK on LPG (and we assume LPG calibration really was OK) and the only setting you changed was reference pressure from 1.1 to 1.5 bar (and you haven't run autocal) it might be a good idea to change ref pressure back to 1.1, or calibration on LPG will be richer than before. On an older system setting 2 cylinder banks can affect a bit more than just allowing the twiddle factor for bank 2 but since the thread is probably confusing enough already I'll just say it is necessary to set 2 banks, even if there is the chance of doing so effecting how it runs on gas a little.
Simon
Nice pics Super4.
A bit of clarification on my last post...
I wasn't implying the vehicle will be running 25% rich or lean if actual pressure is different to reference pressure.
Calibration can still be perfect it software (reference) pressure is set to a different pressure than actual pressure, just that behind the scenes the ECU will be applying a more positive or more negative pressure compensation than it would if actual and reference pressures were exactly the same. I added more info on this too , explaining why installers sometimes have good reason for setting reference pressure different to actual pressure.
The info/pic more recently brought to light on Zavoli reducers (MUST having to be set at 1.2 / 1.5bat respectively for N / S reducers) agrees with what I said about Zavoli reducers, unlike the majority of reducers, being far less pressure stable if the allen key adjuster is adjusted to outside of 1.2 / 1.5bar.
The LPG ECU doesn't look directly to lambda readings at all during autocal. Autocal asks you to run the engine on petrol at a set rpm and keep your foot steady on the accelerator even if rpm changes over the whole process of autocal. Under these conditions it first runs the engine on petrol and monitors pinj, then switches to gas and monitors pinj while it adjusts ALL of the numbers in the map (every box in the map) by the same percentage until pinjs when running on petrol and when running on LPG in the ONE box that autocal used as the basis are same.
During autocal, the only reason rpm will fall/rise and/or engine load fall/rise will be due to if there is a different mixture when switching between fuels, however, autocal repeats the process a few times and as it nears correct calibration for the one map box it refers to, engine rpm and load will stay nearer to the same when the switch of fuels occurs, so by the time it reaches it's last comparison rpm and load won't shift when it switches fuels at all - So even though the box on the map that is applied during the early stages of autocal may shift, towards the end of autocalas long as the operator keeps his foot steady on the accelerator, the box that is the basis for the process won't change.
At this point autocal has hopefully set your map so that at least the box on the map that applied to rpm and pinj during the autocal conditions (fast idle maybe 2500rpm maybe 3.5ms pinj) is set properly. This is where it gets a bit more involved and refers to the shortfall in autocal's abilities... Before you ran autocal you will have entered type of injectors in settings, the type of injectors you selected set the default numbers in the map before you even ran autocal and the transition of those numbers across (rather up and down) the boxes in the map is what we refer to as the map 'shape'. Since autocal raises/lowers every figure in the map by the same percentage, autocal doesn't change the shape of the default map. The shortfall with the default map revolves around the fact that at best it's shape could only ever be an average map, where average means best attempt at suiting the average vehicle...but this default shape probably won't suit even one specific model of vehicle. So ultimately having ran autocal the user must then still change the map manually to make the shape of the map suit the specific vehicle... After running autocal, you should still do manual tuning.
TBH I don't even run autocal's anymore except on systems that demand that it is run before allowing normal operation (BRC and ESGI two such examples). It can be quicker to manually select all the numbers in the map and adjust all of the numbers in the map by a percentage (or even not a percentage, I prefer to work with linear changes because in my experience default maps have numbers too low with too great a map slope). 2500Rpm with lower than idle pinj isn't really a much seen real world operating condition, so if I change all numbers in the map by a percentage or figure at all... I might do my first ever switch to gas on a new install under similar conditions to prevent the engine stalling due to a system that at first contains only air but I'm unlikely to get as much insight into how much of the map will look from these conditions - which pretty much says it all as to the value of autocal on a lot of vehicles. P38's / injected Rover V8's are such low demand that you'd probably get away with just running an autocal, but still the results of just adjusting pressure reference and running autocal without doing any further adjustments might mean trims/mixture is less correct than when you started out.
SImon
Gov might have a point if they say 'Youre running your cars a bit cheaper, you can afford to pay more for domestic electricity now, and transport is good for the economy, especially now it's green, etc etc'.. But I largely agree with your point on this, as in people won't stomach raised domestic or industrial leccy prices even if transport costs are offset by it. Still, you won;t be charging a future electric car with 300 mile range from a 240v 13 amp socket and any special socket wired to your house to charge an electric car could very easily be fitted with it's own meter... sorted as easily as that. Domestic and industrial leccy the same price as now, car charging leccy to include 70% duty?
Yes a 2.0tdi has more bottom end torque, but I don't think it's fully fair to say this is 'accessible power' because the power band of diesels is generally much shorter than that on a petrol and inside/outside that power band equates to the engine making all/nothing power. The petrol has a wider power band and at least will make power at 5000rpm, furthermore that power band comes in and goes out more progressively. To really push both cars you'd need to do a similar number of gear changes, it is perhaps no coincidence that 6 speed gearboxes became more sought after as diesel engine power bands got more all/nothing... but you could probably get away with fewer gear changes if instead of the 2L TD you had a 3L petrol n/a which might cost a very similar amount to run. It's also not fair to compare what's wanted for road cars to what's wanted for race cars but the point about an n/a petrol of same size and same bhp as a td diesel generally being capable of going faster around a track probably does say something about what type of engine is more flexible in terms of power bands, and throttle response is surely another aspect of nice drive-ability?
Depends on what we call very recently. It doesn't seem long ago that diesels didn't have turbos, now we have lots of run of the mill factory petrol turbos such as 1.0 Ford Ecoboost engines fitted in Fiesta's etc and not designed to be high performance... but would certainly show up a 1.0 turbo diesel.
Agreed on short trips no good for diesels. Ignoring for the moment the other points on stink and noise, lack of long journeys damages diesel dpf's and egr's. That very low rpm torque diesels are so good also implies serious engine vibration on diesels with less than 5 cylinders, which is why they need dmf's, but is also the reason they break dmf's much more regularly than petrols, and dmf's are rather expensive... In the comparison between the 2L TD and the 3L petrol above, not much guessing on which would be more likely to need a dpf, dmf, egr. Like you say, stop start driving in diesels can be a false economy. Until recently I though Adblue was something necessary to brake down the crp in chemical toilets. Just reminded myself of my mate who has some unusual greetings such as (first ever sentence to a stranger) 'Have you had a sht this morning?' and (to old mates) 'Long time no see, are you still driving that old sh*tty toilet around?' I can imagine what he'd say to anyone pouring adblue into a car he didn't like lol.
Simon
The option to start on gas will be shown in modern software even if your ECU's firmware is too old to support it.. The option to start on gas may or may not actually work.
You've got to press enter for any changes you make to stick.
As you were told by Jaymic, if you make any changes to the pressure setting you will have to do a full re-calibration. The pressure setting is the pressure at which the system won't factor in any compensation for pressure when calculating gas injector pulse duration, i.e. if actual pressure reading is the same as the reference pressure you set in software it doesn't need to factor in any compensation for pressure being actually higher or lower than your reference pressure. A higher actual pressure than reference pressure will result in the LPG ECU pulsing gas injectors for less time and vice/versa. So, if you make changes to the reference pressure you also have to do a full remap. If you simply change reference pressure from 1.1 to 1.4 bar without doing a remap, the system will compensate for what it now sees is an under pressure situation by pulsing injectors for longer duration (1.4/1.1 = 1.27), so we might expect your mixture to be richer by around 25% unless you remap.
AEB systems are particularly good at compensating for pressure differences accurately. The following isn't to say that it would be a bad idea to change your reference pressure from 1.1 to 1.4 and re-calibrate but is something to consider especially if your system is older... Some of the older AEB systems don't allow you to set the pressure at which the system will switch back to petrol, on such systems (and behind the scenes) the change-back pressure is around 50% of the reference pressure, so that might be 0.55 bar with reference of 1.1 bar and 0.7 bar with reference of 1.4 bar. Your reducer is just about up to the job for fuelling a Rover V8 flat out but might expect pressure to drop a bit when flat out. If you set ref pressure to 1.4 bar, and if other factors are also at play, you may find it more likely to switch back to petrol when you put your foot down even though it might have been perfectly capable of running your engine flat out without switching to petrol. While (again) if you change that figure you'll have to do a full recal anyway. Save your config before making any changes anyway!
Simon
Imagine what the world would look like if 100% electricity came from renewables. Imagine how much extra battery capacity would be needed to store power from renewables... or if we're talking grid storage in terms of batteries in electric vehicles, going to be bed at night thinking you've got X range in your car and waking up to find you have half X range in your car and it would take 4 hours to charge back to X range.
Imagine comparing a 1400cc diesel turbo to a 1400cc petrol or LPG turbo, or a 3000cc diesel turbo to a 3000cc petrol or LPG turbo. Comparing a turbo to a none turbo isn't fair but I do remember a track test (by the likes of Top or 5th Gear) that compared a BMW 3L turbo diesel to the 3L normally aspirated petrol version of the same car and the petrol version bet the lap time of the diesel even though it had about 20% less bhp. For a fair test you'd have to be comparing the 330 turbo diesel to something like a modern M3, then come back and tell us which car was the nicest to drive ;-)
Easy to tax electricity in the same way as petrol really - If 1kwh costs X, force the electricity suppliers to charge gov's 70% duty on top of X.
My bit about China and India wasn't intended to be taken completely literally but raises a concept...They missed the boat in terms of early industrialisation, it may be cheaper for them to proceed in the same way the West did and go through the smog stage etc but they'd be doing it on a bigger scale and consuming resources that the Western way of life has depended on for decades, so perhaps it's just as well that they should be at the forefront of developing new clean technologies in order to progress even if it that slows the progress.
I would've clicked 'Like' on the last 4 posts but the facility isn't there ;-)
Had a similar discussion/argument with the mod of a UK Subaru Legacy forum (http://www.uklegacy.com/forums/index.php/topic/144446-tomorrows-world-of-motoring/) before getting myself banned for telling it how it is on a different subject.(explained below). If you read the thread bare in mind that the mod DAZRSK had previously taken every opportunity to criticise LPG conversion over various threads and it seemed to me he started this thread as yet another way of taking a pop.
A few owners of Subaru's all with twin scroll turbo's all fitted with BRC LPG equipment all had the same problems which their installers couldn't sort out even after many return visits. I predicted what the problem would be and drew a few conclusions about the systems and the installers. Everything I said was proven to be true but one guy with the problems took exception to my drawing conclusions (that were correct) because they painted his installer, who was his mate, in a negative light. He threatened the forum with legal action and implied his installer and BRC would also take legal action... He went from saying things like 'I thank Simon profusely for all his help on this' to threatening the forum resulting in my being banned and the whole thread deleted, but only after his problems were solved lol. Had any of the threats been directed at me I would have been happy to go to court with them.
I'm on good terms with the boss of the forum who banned me (not DAZRSK but I'm not on bad terms with him either), the boss is just scared of the hassle he's been threatened with.
Diesels sound crap, kick out crap from the exhaust and are crap to drive.
The electricity used to charge electric only vehicles (and run everything else that runs on electric) comes mostly from power generation plants that burn fossil fuels, this is likely to be the case until (and if) fusion reactors are invented. If fusion reactors were in place tomorrow the electrical supply infrastructure would still need upgrading before the majority of homes could have an electric vehicle.
Countries need revenue from vehicle fuel tax on the one hand but want everyone to be green on the other hand. If it currently costs a motorist something like 15p to drive a mile in a car and government get half the 15p in revenue, that's 7.5p gov gets for the average mile driven. As a nod to green gov allows reduced taxation on green fuels such as LPG and electric vehicles. If there comes a day when everyone runs an electric vehicle, the electric will have to cost at least 7.5p for every mile driven plus whatever extra needs to be factored in to cover the cost of upgrading infrastructure.
The savings enjoyed by running electric vehicles may only last until the electric vehicles get better and start to become more mainstream. While-ever anyone produces petrol, LPG will also be produced and governments that like to nod to green will tax it less heavily than petrol. We could even see a situation in future where it costs less to run a vehicle on LPG than electric... Electric cars are not totally clean, they shift the problem from vehicle exhausts to power station exhausts. Then we could talk about (ref Brian's post) what it takes to get enough lithium to produce batteries for all these electric vehicles and copper for electric cables and transformers.
In the future maybe we'll have to take our dead in our electric cars to recycling centres for rare earth element extraction lol. One of the biggest problems with regards oil use is the rising demand from developing countries like, say, China and India. What would happen if developed countries took a hard line on this - 'Sorry China / India, we developed first and have become accustomed to our way of life, but we're not going to let you do the same as we have/do with oil because there isn't enough to go round'. War? OK. So what if we say to oil producing countries 'We know you only have oil to offer and have based your economies and standards of living on selling oil to the West but we're not going to buy any oil in future, sorry'. War? Well maybe they'll start turning oil into more plastic products such as ships ,etc which become much cheaper than current metal ships but the new products bring problems of their own (plastic on the sea bed etc). Then we might say 'Sorry still no good, you're still causing pollution'. Is it war yet? If only we had nuclear fusion, and that Star Trek technology for producing food etc out of thin air (that runs on lectric).
Simon
Only thing is, at higher rpm in neutral the engine manifold pressure will be lower than at normal idle speed, and since gas pressure is relative to manifold pressure gas pressure should be lower at high idle speed so less gas should escape from any leak.
Yeh that's good!
Must have been quite a leak on the 4mm pipe. Even without a spring clip or even if you cut part way through that pipe would still expect the pressure sensor to read system pressure.
Simon
As said, a bit of a leak (hiss when you bend pipes etc) on the 4mm pipe between Matrix and pressure sensor is unlikely to be enough to cause a low pressure reading at the sensor. But you'll want to eventually fix this problem anyway and it would be a good idea to fix it now so you can at least rule this out.
Whilst on the subject of the errors page - The software may show an errors page but we don't yet know if your ECU/firmware are new enough to support error reporting. But it's worth checking to see if any faults register for gas vapour temp sensor... If the ECU picks up on such error it will switch back to petrol anyway.
Recap...
You have ruled out some potential causes such as blocked liquid filter and solenoid. It is very unlikely that the tank pickup pipe has come off, far more likely that there's a problem at the front end such as faulty reducer. The leak(s) as you described them seem to be inconsequential.
Simon
I think it's unlikely that this leak will be cause of the system reading low gas pressure - If the leak was bad enough to have sensor read low gas pressure you'd certainly have known about it before. Also, any leak that you can start and stop by moving pipes probably equates to only a small fraction of the gas that the engine could use if you put your foot down.... so although it might hiss and stink and generally be less than safe, such leak is probably negligible in terms of a proper functioning reducer's flow capability. The one exception would be if you pulled the pressure pipe to the pressure sensor just about all the way off but then you'd smell and hear it.
With the front solenoid guts removed there's still the tank solenoid, so if you create a leak on the vapour side gas will leak for quite a while (until liquid gas between tank and reducer is used up) before dying down.
You can't use petrol hose for LPG.
5mm or 6mm internal diameter pipe between injectors and manifold, 4mm internal pipe between Matrix injectors and pressure sensor.
Simon
super4 wrote:
Have checked wiring and things I can get to, managed to get 12 volts to the solenoid on the reducer which sort of worked but did not seem as active as the one on the tank - it may be that the connection I was making was not very good. But what I want to ask is - does the pressure come from the simple fact that the gas in tank is under pressure and therefore makes its way to the intake manifold provided solenoids etc allow it or does the pressure get built by the reducer in addition. If the pressure is in the system all through then presumably I have a blockage or as suggested, a solenoid simply not opening ? Is it as simple as that ?
The tank solenoid will likely be a lot louder than the front solenoid because it is on the tank.. Tap the tank with a screwdriver and it will make a lot louder noise than if you tap the front solenoid with a screwdriver. Plungers in solenoid posts do get fouled with crud / heavy ends but if they open at all they usually flow enough to allow the engine to run OK and it's a similar story with filters. But you could rule out both the plunger and the filter by simply removing them temporarily to see if the same happens with them removed. Even if removing them seems to effect a cure (which might point to plunger post or filter problem) the real problem could still be voltage drop when the injectors pulse for longer duration (could still be main power feed issue).
Simon
Orangebean wrote:
Handy hint, not LPG related, but...
Wheels stuck on hubs- loosen wheel nuts (sufficient to allow wheel to wobble on hub but not fall off). Drive car forwards and backwards a bit while turning steering from lock to lock.
Most of the time just loosening nuts and turning steering from lock to lock will do it.
Much easier on the back!
In my boy racer days I followed a group of lads who were in a mk1 Escort down the A1 at 100mph, they pulled up due to steering wheel wobble, turned out they'd changed a wheel earlier but can't have done the nuts up properly because 3 nuts were missing and the one remaining was nearly at the end of its threads!
Sorry I missed this thread until now.
Unlikely to be a case of solenoid not opening enough to allow enough flow of liquid gas for idle but not enough flow of liquid gas for blipping the throttle or light acceleration... Unless the electrical feed to the solenoid is intermittent, in which case the solenoid might close when the throttle is blipped or in light acceleration - but unless this was due to a main power feed problem (to the LPG ECU) it would more likely be due to coincidence.
I have known plenty Zavoli reducers fail in a way where the maximum gas flow is severely restricted, in some cases the restricted gas flow has been enough to maintain vapour pressure for idle but for no greater load than idle... so blipping the throttle or light acceleration would cause pressure to fall away very quickly (can't maintain pressure of volume throughput is restricted, so pressure falls away, system senses lack of pressure and switches back to petrol). The situation described here would call for a new reducer but this may not be the case and it's worth doing other checks first.
The gas vapour temp sensor will need fixing, it's worth checking the solenoids and for issues such as bad main power feed / earth.
You could monitor voltage to the solenoid(s) while switching to gas, at idle on gas, and when you blip the throttle. The injectors pulse for longer with higher engine loads (such as when blipping the throttle) soif there's a bad main power feed to the LPG ECU the extra current drawn can cause voltage to all LPG components to lower which could cause solenoids to close or sensors (including pressure sensor) to read incorrectly.
After the system has beeped and switched itself back to petrol you could read vapour pressure on screen again, N/A (not applicable) means no pressure... If you do a pinch test on a vapour pipe (or disconnect a pipe) you'll know if this seems to be a true or false reading. False reading points to pressure sensor, voltage or ECU problem. True reading points to solenoid, voltage or reducer problem.
Another thing about Zavoli reducers is that they only really like to work at the pressure for which they were designed (1.2 or 1.5 bar depending on model). Like other reducers they have a pressure adjusting screw but on Zavoli reducers if you turn pressure down they tend not to be capable of flowing nearly as much gas (throughput) as at standard pressure.
This is all assuming the feed from the tank is good - If the tank were outputting vapour instead of liquid (on a single hole tank, particularly 30 degree tanks) if the flexible pipe that picks up liquid from the bottom of the tank has come off inside the tank the tank will output vapour. The reducer needs to be fed liquid gas but might flow enough for idle if fed vapour.
Simon