Toyota Prius 2nd Gen. - converted to LPG hybrid

Yes it is... Damn 2600$ roadtax a year being poored into my Volvo...

I verified my roadtax will still be zero for the next two years for the Prius.
But putting it in without declaring it will cause issues with the APK/MOT/whatever-you-call-a-yearly-inspection-of-the-car-with-a-report-going-to-the-government... That may cause more problems than it's worth...

Old thread, but a goodie !! I don't recall if I already posted congrat's to our Romanian PC'er ... but WAY to GO! Reminds me of my '70's Ford Van that my gramp's sold me. He'd removed ALL the smog junk, so it was cheeper to simply mod to propane. When it's the only fuel (in stead of dual fuel) then California exempts you from smog checks. The mpg went down from 13mpg to 10mpg ... but propane is perportionally less expensive. But MAN !! ... you can NOT believe how clean your oil stays, running propane. VERY nice set up, and I'd consider the same thing if it weren't for fear of how such a set up would confuse the various fuel delivery ECU's.

I have made up my mind and took my Prius to installation today morning. They're installing IV gen LPG device with Prins Keihin injectors (with warranty for next 200 000km). Total cost €1250. I really do not have any idea for the rest of the components, Mandrei83, am I doing the wise choice here going for Prins?

1250EUR they are LOTS of moneys. 650EUR (shipping included for everything) it's only the cost of the latest hardware from Autogaz Poland (I have Stag-300 Premium on my Prius) and the rest is the working hand. Then will cost the homologation in your country - make sure you will be legal with your install!

For me, the whole installation package looks quite costly. But, if you want it faster and in your country, go for it like that!

Yes, that was quite a lot, I must agree. But since I don't have the skills and equipment, and Romania is 1970km from me I really had no other choice. Still happy about doing it and regret I didn't go for it months ago.

The installation was made by professionals, I have also registred the LPG device officially at local DMV (fee was €19, i.e around $25). The Prius was installed 62L gas tank and I received the car March 3rd. Still driving the first tank, already 750km. I managed to fill it with 52L (€40.04 total). The wierd thing is that all four gas tank level green LEDs are still on, probably something is wrong with the indicator(s). Also, since then the petrol tank indicator have been decreased by three bars (prior to installations after 230km two bars were gone, now it shows me that half of tank of petrol is left, the total mileage after filling the petrol tank is 980km).

The LPG system automatically turns on after about 1-5 minutes engine is started, it really depends on the outside temperature and whether the engine is still warm from the previous driving or not. I could see really good petrol save for the one's who have the garage.

Have you calculated how much km must you drive until you need to refill your petrol tank? And how much km can you drive with your 34L gas tank (27-28 gas filled in)?

The wierd thing is that all four gas tank level green LEDs are still on, probably something is wrong with the indicator(s). Also, since then the petrol tank indicator have been decreased by three bars (prior to installations after 230km two bars were gone, now it shows me that half of tank of petrol is left, the total mileage after filling the petrol tank is 980km).

If you are talking about STAG, the problem with LEDs may be the wrong setting in the software. You have to see what type of gas level indicator you have on your multivalve in the tank and make appropriate setting in the software. I think the installer simply chose the wrong option in the software this is why you always have those three bars. Three are like three gas level indicator types in STAG. The software of STAG also could be better. If you come into a settings section there is no such option like "save setting". If you come into a section and leave the section you previous selection is gone. You have to return, make the same setting again and leave. It could have been that the installer did not notice that and the software had reset the original setting for gas level indicator. I suggest that you buy a STAG cable.

Also Andrei, what I saw from your pictures you have those quick Valtec 34 injectors. They are very vulnerable to poor gas quality. Make sure you change filters often or even install 2 filters. They bite the dust due to poor LPG quality and you can't fix them. I would have bought HANA 2000 instead of Valtek 34.

My message mis located, again. A product on the market, called STABLE, keeps gasoline fresh.

Harris Berkowitz: the settings for each LPG tank are different. I could tell you what settings I have on my LPG tank, but it wouldn't help you too much. My suggestion would be to do below things:

1. Make sure that the LPG tank is empty and fill inside exactly 5 liters of LPG. Then trigger the first LED to be powered on. Then add another 5 liters and trigger LEDs to the next level... and continue doing this few times. You can fill the tank with LPG and estimate the intermediate steps between level-1 and level-5 when the tank is full.
2. You can start with the full tank with LPG... then drive the Prius constantly on highway/road and set the intermediate steps until the tank will get empty. I would recommend 1 instead 2. The calibration of the LPG tank is quite personalized, as I've said... and it's done manually.
3. Any other calibration suggestions are welcome!

andyprius: STABLE is the equivalent of LPG in US? Or you have now a commercial equivalent gas, instead LPG as we're having it in EU?

Just a small update regarding the filter from the LPG system: I've changed mine after 40.000Km, it was a little bit yellow, but no problems with my LPG kit so far. I believe my friend which has mounted me the LPG system has already 100.000Km and he didn't changed anything in his LPG system. Basically, what most of manufacturers say, is that you need to do a "revision"/replacement of the filter at every 15.000Km, other else, you loose the warranty of the LPG ECU. What I did to my ECU? I didn't care about the warranty and I've reset manually the ECU firmware through the LPG SW interface the number of kilometers. It started to buzz at each 15.000Km, from what I remember, remembering me that I have to do the replacement of the filter. IGNORE.

Now, regarding the car's warranty: mine is not anymore in warranty and, what my Toyota representative said is that you loose only the warranty of the engine, by installing this conversion kit. I didn't care too much about this, as Prius is a reliable car and I didn't hear people to have problems with the engine. If someone believes that the removal of the warranty was abusive after installing this LPG conversion kit, I would suggest to sue the Toyota representative or even Toyota. These kind of things are quite common in US and there is a big chance to be the winner!

Sorry to all of you for replying so late, I wasn't very active on this forum in the last months...

Just so there's no confusion, the product name is actually STA-BIL.

hello mandrei, name is George I live in Westland Michigan I just noticed your post the other day, myself I grew up in Romania, just recently got a prius, been lurking on this website for a minute as a guest, bought a car in the meantime, and though allready an awsome vehicle and total overkill on fuel economy as it is, particularly in my area I had planed on making it better since before I bought it just because I can.
I must say I am impressed with your build, true romanian style, get the parts, figure it out, who needs a certified, insured properly trained teck, and waraty, if it breaks I'll fix it again, mostly what I like about your upgrade is the cost return, most other updates I seen are just not cost efetive, therefore I am interested in doing ther same myself.
you were asking about fuel costs in the US, its an odd one thats for sure , diesel is usualy significantly more expensive, a 40mpg vw gives you the same $/mile as a regular gas car, although people constantly bitch about fuel prices, it is not expensive enough for drivers to be conscious about theyr needs, most would rather have a 12mpg truck than get caught dead in a prius, I admit i am no different, took me a while to grow into it, besides toyota totaly screwed up marketing this car here.
as for lpg, there is plenty of infrastructure, again most people are too ignorant to notice it, myself I run lpg toyota forklifts at work, there is a reason for these indoor machines running on lpg, a properly tuned lpg motor emits, carbon dioxide and watter vapor, so anybody concerned about emissions, quit it, co2 is a greenhouse gas and so is watter vapor but no toxics, back on topic, the forklifts take interchangeble tanks I believe they are 8 gallons *3.78=liters thing with lpg, unlike gas I have been buying it for I believe $18 for the past 3 years, never fluctuated, and depending on how much you buy, you can negotiate try doing that at a gas station. I always stock adozen tanks so in that sense I have my own fuelstation, we load up the truck with the empties and exchange them at the main distribuitor in this area from time to time, which happens to be a mile from work, they also deliver if you call them, or you can set it up that they stop by once a week and replace your empties.better yet I have an account, I get a bill at the end of the month.
however I have refilled them at various hardware stores on ocassion, for a couple extra bucks and there are a dozen of those on my way to work, anybody telling you there is no infrastucture expects to see propane at a gas station, comming out of a nosle, truth is most gas stations sell propane tanks for barbeques, (dumest thing I ever heard of, might as well use the stove) however it is retardly marked up, those tanks do have the same threaded fittings as the forklifts, there are people in rural area where pipelines dont reach that have their own tanks, to run their stoves and furnaces
At the moment gas is $3.something but thats just because the presidential elections, not too long ago it was $4.something and it will be up there again right after the hollydays , diesel still is $4.5/gal,
I only had my prius for a couple fillups now, 7 gallons about $24, I recon I'd get about the same miles out of an 8 gal propane tank, for $18 thats $6 saved 100 fills to break even about 35000 miles car only has 40 k now well worth it I think, but wait till gas is back to 4.5 * 7gal=31.5 i think to fill, propane would still be 18 thats $12 less a fill about 18k to break even, definately feasable compared to plug in, I'm in, though I may need your help sourcing the parts, I knew lpg conversions were popular in europe, figured thats the place to source parts, looked into it a while back before the prius, I can get a forklift lpg system for about 800 but it wont work with all those electronics, its just a simple vaporiser system, computers wont know what to do, id be fine on an old carb engine not a prius, I have some reading to do looks like the system you are using taps into the toyota injectors, do you know if it employs a fuelpump and a return line?
I'll check back in a bit

hello mandrei, name is George I live in Westland Michigan I just noticed your post the other day, myself I grew up in Romania, just recently got a prius, been lurking on this website for a minute as a guest, bought a car in the meantime, and though allready an awsome vehicle and total overkill on fuel economy as it is, particularly in my area I had planed on making it better since before I bought it just because I can.
I must say I am impressed with your build, true romanian style, get the parts, figure it out, who needs a certified, insured properly trained teck, and waraty, if it breaks I'll fix it again, mostly what I like about your upgrade is the cost return, most other updates I seen are just not cost efetive, therefore I am interested in doing ther same myself.
you were asking about fuel costs in the US, its an odd one thats for sure , diesel is usualy significantly more expensive, a 40mpg vw gives you the same $/mile as a regular gas car, although people constantly bitch about fuel prices, it is not expensive enough for drivers to be conscious about theyr needs, most would rather have a 12mpg truck than get caught dead in a prius, I admit i am no different, took me a while to grow into it, besides toyota totaly screwed up marketing this car here.
as for lpg, there is plenty of infrastructure, again most people are too ignorant to notice it, myself I run lpg toyota forklifts at work, there is a reason for these indoor machines running on lpg, a properly tuned lpg motor emits, carbon dioxide and watter vapor, so anybody concerned about emissions, quit it, co2 is a greenhouse gas and so is watter vapor but no toxics, back on topic, the forklifts take interchangeble tanks I believe they are 8 gallons *3.78=liters thing with lpg, unlike gas I have been buying it for I believe $18 for the past 3 years, never fluctuated, and depending on how much you buy, you can negotiate try doing that at a gas station. I always stock adozen tanks so in that sense I have my own fuelstation, we load up the truck with the empties and exchange them at the main distribuitor in this area from time to time, which happens to be a mile from work, they also deliver if you call them, or you can set it up that they stop by once a week and replace your empties.better yet I have an account, I get a bill at the end of the month.
however I have refilled them at various hardware stores on ocassion, for a couple extra bucks and there are a dozen of those on my way to work, anybody telling you there is no infrastucture expects to see propane at a gas station, comming out of a nosle, truth is most gas stations sell propane tanks for barbeques, (dumest thing I ever heard of, might as well use the stove) however it is retardly marked up, those tanks do have the same threaded fittings as the forklifts, there are people in rural area where pipelines dont reach that have their own tanks, to run their stoves and furnaces
At the moment gas is $3.something but thats just because the presidential elections, not too long ago it was $4.something and it will be up there again right after the hollydays , diesel still is $4.5/gal,
I only had my prius for a couple fillups now, 7 gallons about $24, I recon I'd get about the same miles out of an 8 gal propane tank, for $18 thats $6 saved 100 fills to break even about 35000 miles car only has 40 k now well worth it I think, but wait till gas is back to 4.5 * 7gal=31.5 i think to fill, propane would still be 18 thats $12 less a fill about 18k to break even, definately feasable compared to plug in, I'm in though I may need your help sourcing the parts, I knoew lpg conve4rsions were popular in europe, figured thats the place to source parts

just reading through the stag manuals, I asume you got the 4 cyl version, I read somewhere stag 200 is suitable for up to 90 hp, I asume you did your research, and there is a reason as to why you chose the 300 premium instead, I wonder if it is not overkill, I am not entirely familiar as to how they meter the fuel delivery but it apears that the lpg computer intercepts the oem injectors signals and adapts and resends to the lpg injectors therefore the car is cluless that it runs on lpg instead, question for you : did this kit come with a wire harness or you had to build it based on the skematics, in other words, does autogas make a kit for the prius or is this a generic 4 cyl kit, that you adapted to the prius?

uhh my ears are smoking allready, looks like the polish got this realy dialed in, china's got nothing on them, than again, they been doing this for some time, truth be told I knew if one considers lpg europe is the market to get your equipment from, I need to give those folks a call, I believe they are about 6 hours ahead, so far I am impressed with what I have read this is no toy nor for your average ' I can tint my own windows " diyselfer, I've been plaing with wrenches since I was still in diapers and still freak out when I see a computer hooked up to a car, I hope they have a preprogramed prius version or maybe I can download your settings to start, its a lot to take in.

So, how are the thoughts after some time using it?

From my knowledge, LPG injection into the intake manifold in Prius wouldn't be a good idea... The car uses the modified valves timing to work in Atkins cycle... The unburned LPG would get directly into the exhaust damaging the catalytic converter.

15*C for the switch is a bit low as well - the membranes in the vaporizer would get cracked very soon.

As I understand the modified valve timing, the part of LPG and air mixture is pushed back into the INTAKE manifold (burned in the next cycle), I don't understand how the unburned LPG would end up in the exhaust?

The only problem I see with OP LPG conversion is valve lubrication, in general all Toyota motors need extra valve lubrication system when they are converted to LPG, so I'm curios how things are after some time of using LPG?

If that is the case, there will not be any problem. I was however under impression that the Atkinson cycle is Prius achieved by having the exaust valve opened when the piston starts moving up.

IMHO lubrication is a myth and does not help at all. What one must do is check the valve clearance much often than when running only on petrol. I would imagine 30kkm/20k miles interval would be good to have it checked.

well I was hoping to hear back from the op by now, anywho gas is pushing $4 a galon by now, go figure, honestly I am not too woried about it, checked with my old man, propane is $19 a tank, plus tax, about $20 for 8 galons, saves about $8 a fill, the savings are not substantial but it does seem to recover, unlike plugin, seems to be more of a choice, by the time you recovered some cost you need new batteries, thats if all went well, a propane kit should outlast the vehicle and than you can swap it on the new one, I plan on calling autogaz tomorow, see if they are open given the hollyday, ahd hopefully somebody speaks something other than polish, wonder if they have new products, and if its still about $600, matter of fact I'm about 6 hous behind, I best get to it

Actually, it is the intake valve that remains open during the initial compression stroke.

JeffD