brendangeorge

Propane is 112 - I have seen 108 quoted for LPG. I believe our LPG is propane. Bren

Hi Alan I will try and check but it may be the weekend before I can - I don't think it will be anything like 2 amps - with the ignition on if I remember it draws 6 amps. If you go the solar route you will need to cable it on to the battery (with an in-line fuse etc), Cheers Bren

Hi Chris I would be a very tight fit in a Micra - I am sure it would be a good laugh videoing me trying :) You are correct about the car needing more LPG than petrol for the same power - 22MPG on petrol and best case 20 MPG on LPG. This is because ss you quote LPG only has 73% of the energy of LPG. Bren Hi LPG has a lower calorific value than petrol or diesel but also is higher octain & burns more efficiently . Surely this would make up some way for the lower energy? or am I missing something. Yep it is the energy (calorific) value that counts - there is no octane in LPG it is propane. Be careful about octane rating and RON (research octane number) they are used to define how resistant to knocking (pre-ignition) fuel is. Bren

Hi Chris I would be a very tight fit in a Micra - I am sure it would be a good laugh videoing me trying :) You are correct about the car needing more LPG than petrol for the same power - 22MPG on petrol and best case 20 MPG on LPG. This is because as you quote LPG only has 73% of the energy of LPG. Bren

I really hope so Mark. Unfortunately I am not sure the timing and electronics etc are the problems - with all the tools available it is possible to sort that out if you want to pay. The big challenge is the direct injection system - the petrol injectors go straight into the cylinders so they need to be cooled when running on gas or possibly you could run on a mix of petrol and gas - assuming there is somewher you can fit the gas injectors - but this would kill the economics. You will then need to sort out the ECU to drive all this. As an engineer I expect some clever so and so will come up with a solution and there is hope as most petrol engine manufacturers move to DGI the LPG converters will have to keep up. Cheers Bren AC stag are already doing DGI or DPI systems if you go on their website there is a list of cars they do.AC400 DPI controllers All they need is the timing stats which are normally released 7 years after first production to develop a system for a specific model. Leon from Profess will let you know more about it if you pm him. I spoke with him about it when I was last there as a mate is thinking about a 460 or 600. I talked to STAG about GDI engine conversion and they stopped talking when I mentioned 460. I just had a read around the subject and I can see several problems. You have to inject the LPG into the manifold (plenum) where the air goes in. You need to cool the petrol injectors (with petrol) and so have to burn petrol and gas at the same time. The DGI engines are a big leap in technology and complexity - (look at GDI on Wiki) in order to reduce fuel consumption and emissions so conversion will be tough. I see that there are some GDI conversions available - but not many. It would be great to here if Leon thinks it will be possible to convert a 460 in the near future. Bren

I really hope so Mark. Unfortunately I am not sure the timing and electronics etc are the problems - with all the tools available it is possible to sort that out if you want to pay. The big challenge is the direct injection system - the petrol injectors go straight into the cylinders so they need to be cooled when running on gas or possibly you could run on a mix of petrol and gas - assuming there is somewher you can fit the gas injectors - but this would kill the economics. You will then need to sort out the ECU to drive all this. As an engineer I expect some clever so and so will come up with a solution and there is hope as most petrol engine manufacturers move to DGI the LPG converters will have to keep up. Cheers Bren

They are an impressive looking car aren't they? Bit worried about all the gizmos though, as the car gets older, similarly with the 430. Yep very impressive - and I am also concerned about the crash sensors and power steering etc - some of the faults reported and bilblical repair costs are worrying. Also there are so few on the road there will be none to speak of being broken for spares when they get old. I was expecting to lose my 430 this year but managed to keep it on the road (I will post about it later) so the 460 will have to wait a bit longer. Bren

Hi Michael I am 100% with you - I would have gone with the loss of 1" of boot height to get a 100l tank in if my installer had given me the option (especially with hindsight) the extra 50 miles or so range would be very useful - a good thing to consider if you are thining of converting. I carry a spare because of the shocking state of the roads today and I am not keen on tyre weld unless as a last resort, so my boot is almost full anyway. I am a Yorkshireman so a tight git by definition so cannot completely support the "I would drive it anyway proposition" :( - who am I kidding. I expect to be in a 460 in a year, or two at the most, so will be buying petrol then :) Bren

Oh.... is that what that is.... by the way there should be a window sticker to warn would be thieves that the radio is coded. Paul I'll have a look for that tomorrow. Mike You may want to include a link on how to remove the radio - when they see it takes more than 30 secs they will p%ss off and rob somebody else. Bren

Lovely stuff JPJ and Michael - I can get 272 miles from 65.39 liters but usually quote 250 from 65 - the tank in my 430 is 82l and I can use about 65l - a little more in the summer and less in the winter. I see you have a 400 - what size tank do you have and how many miles do you get from its usable volume? I was looking to compare the 400 to the 430 - my gas system is a BRC. It looks as if you chaps get about 4.3 miles per litre and I get about 4.15 from the back of my fag packet. Does this sound correct? On petrol I get 4.8 miles per litre - looks like getting on for a 40% saving as well. Very cool. Cheers Bren

No sweat Amber - as can be seen from my reply to Mark I had two of the beasts and did not know about the code function. It does seem a redundant feature - especially when there is a crack available. Cheers Bren PS does the anybody know if the 430 has a code function for the stereo/sat nav?

Amazing Mark - I had two MK4s and did not know there was a code function. It would be really annoying to go to the trouble of knicking a Lexus stero etc and then finding out it needed a code. I don't think the 430 has a code but what would I know I have only owned it for 11 years :) Cheers Bren

Hi Anthony What you are suggesting will work but I would caution against it. You car battery is not designed to be discharged (flattened) to do so regularly will shorten its life. Car batteries are designed to provide a lot of current for a short time (during cranking) and not to be discharged deeply - depth of discharge and number of charge discharge cycles determine the battery life. This is why float charging should be used when not using your car for a period of time. Also you will still need to charge your battery - unless you drive long distances - after you let if go flat. If you keep it in a garage and can float charge it (CTEK charges are £30 to £50 on ebay) and your battery could last 6 years vs a new battery £100 (with a 3 year guarrantee. You can easily kill a battery in 1 to 2 years. Modern cars can be a pain because they are full of electronics (I am an electrical and electronics engineer :)) Cheers Bren

Hi Anthony There is no radio code so you don't have to worry about that. The car will drain the battery if sat for a few days because of all the electronics - so the best thing is to leave it connected to a battery charger that has a float charge function. CTEK are good and I use one. You can also put your charger on a timer that runs it for say two hours a day - it is vital that you do not over-charge the battery or the water in the electrolyte will electrolyse and the hydrogen and oxygen generated will be vented and could be a fire risk - if you cause a spark when disconnecting the charger – also your battery has then had it because you have no way to refill it with water. The possible venting of gas is why you are told to disconnect the battery before charging but this does not help if you do not remove it to another room – just ventilate your garage and you will be fine. Some people sell battery tenders that will provide the float charge function – I think this is just another (American?) name for a float charger. If you do not have a garage and cannot use the charger method there are solar solutions available (assuming the sun shines). It sounds as if you are thinking about removing the battery from the car and charging it separately while you are away – while all the hand books say you should do this – I do not believe it is necessary and I never do – note this comment does not mean I accept any liability for you blowing anything or yourself up because I know nothing J I hope this helps. Good luck Bren

Hi Mike You are spot on with a litre for litre comparison. Running on LPG I obtain 16.3 to 20 MPG - running on petrol for 120K miles my average was 22MPG for a mix of driving - as you point out LPG has 73% of the energy value of petrol. That said if you then take into account the price difference between LPG and petrol you can make a meaningful comparison. To make it simple best case I can get 400 miles from an 84l tank of petrol and 272 miles from 65l of LPG. If you do the calculation I am saving 36.8% of the cost of what I would pay to drive on petrol if I run on LPG. I used £1.34 per litre for petrol and 74p for LPG so the figures will vary by a lot - my last LPG up North was only 65 per litre - so a 30% to 40% saving is very real for me. Bren

Hi Mike, I sent the article to Leon at Profess. My local fillup is 69.9p, 70p for arguments sake. Most of my travelling is within 125 miles of where I live and the most I have paid recently is 72p (71.9) I know where most of these filling stations are but normally never need to use them as I always fill up locally before I make a journey. About 10 years ago I had a Mercedes estate W124 2litre, it had 90,000 miles on it when I bought the car and when I sold the car it had 260,000 miles on her with no engine problems and is still going strong to this day approching 300,000 and still on LPG. The article is full of holes but I will wait any further comment until Leon has got back to the forum. Mike If LPG converted cars were going down like flies I think we would have heard about it. LPG is very popular all over Europe - I believe that in Italy you used to be able to buy a Lexus from a dealer with a conversion fitted. On the back of a fag packet I save about 40% by using LPG and if I drove more economically I bet I could do better. To be fair the AMS web site does say not all cars suffer with problems when converted to LPG and if you look at the list it does not have that many cars on it. They talk about Vauxhall cars on the site but there are none on the problem list (a few big Septic GM lumps by the look of things). The data they present is from Prins so is this a list that they have circulated to installers warning them of potential problems? Bren

There are plenty of errors and wrong assumptions on the link. The price of LPG quoted is wrong - especially up North - in my area near the motroways it is upto 84p per litre but 74/75 is more normal. When I went to Twickenham it was 69p there and 65p at Beaconsfield services. This means the poor economics quoted are BS at best. The challenge with LPG may be the burn temperature - it is hotter than petrol - but to claim that the petrol injected cools the valves is a bit of poetic licence. Most LPG convertible cars have inlet manifolds where the petrol is injected - I am sure we could find a lot of thermodynamic analysis that shows this cooling argument is not sensible. Manufacturers seem to be moving to DGI or some combination of DGI and manifold to meet emission and consumption demands/requirements which will probably be the factor that kills of LPG conversion for new cars. Perhaps the LPG conversion guys can comment here. All cars had to be made with harder/more durable vavle seats when unleaded petrol was introduced because the lead in petrol was the additive that protected them. The comment about additves in petrol lubricating and reducing valve seat wear seems interesting - the additives are there to keep the engine clean and stop deposits causing valve damage. I know two people who ( one MK4 LS400 and one face lift 430) who had valve seat damage and many of us who have done 100K miles with no problems. Could it be that some engine manufacturers are reducing their costs by changing materials and some engines are more vulnerable to the hotter LPG burn - if that is the case don't tell us that LPG is to blame. There is a list of cars that may have problems on the site but no other data - most important being how many of each model unless I missed something. Without knowing if the cars were maintained properly etc it is tough to make an analysis. It would be really interesting to find out the real reason why AMS have stopped carrying out conversions. It will be great to see what Leon has to say because I know nothing. Bren (LPG user and biggot)

Hi My Lord I am not sure where you got 11v to power the display from - if a lead acid battery is showing 11V it is flat. Approximate readings are 12.6V 100% charge, 12.1 V 50% charge and 11.7V not charge - only approximate and with not load on the bat so with a lexus that probably means disconnected. Don't forget a lead acid battery does not like being flattened - it's life will be shortened. If you bat seems weak charge it up before starting the car. Good luck - the correct battery is easy to find for between £70 and £120 with a 3 year guarrantee - people will try and sell you a premium battery but it will probably just have more capacity than is required. Bren Bren your technical knowledge is absolutely amazing, you surprise me each time when you post on things technical. Mike Mike - thanks for your kind words - I have an engineering degree so tend to dig into things and like most people on here don't always take the first thing I am told as gospel. Batteries are a fun topic and are very useful until they let you down when you most need them - usually when it is cold, wet and dark. Cheers Bren

Hi My Lord I am not sure where you got 11v to power the display from - if a lead acid battery is showing 11V it is flat. Approximate readings are 12.6V 100% charge, 12.1 V 50% charge and 11.7V no charge - only approximate and with not load on the bat so with a lexus that probably means disconnected. Don't forget a lead acid battery does not like being flattened - it's life will be shortened. If you bat seems weak charge it up before starting the car. Good luck - the correct battery is easy to find for between £70 and £120 with a 3 year guarrantee - people will try and sell you a premium battery but it will probably just have more capacity than is required. Bren

It seems as if the maintainence worked well (even a web site needs an oil change now and again) because it seems to be running a little faster today :) I was on the road all day yesterday so did not have time for my daily fix. Bren PS I love the truck

Here Here. Could not have put it better. I'll second that emotion. Good luck MJM - I hope you get well soon. Bren

Hi - My local indi fitted a third party replacement for less than the cost of the part from Lexus. The book time is 2.5 hours and as was posted here it only takes 20 mins to swap. I would be wary of a part from a scrapper - you may not know its age, condition or how it was stored. I am on motor number 3 on my 430 after 200K miles. Bren Bren

What do you expect the weather to do it's a Bank Holiday weekend - the damn grass will be 10 feet tall by Tuesday.

Nope JP - the parrot will do it though :)

Pop the offending wheel off and manually turn the hub and listen, as Bluesman said it may be a pad rubbing, caliper may just need a good clean. Obviously get the car safe to jack up first before you remove the wheel Can one of you (JPJSavage/Maduggo) grow a beard and wear contact lenses, I thought for a minute you were giving advice on your own problem. Mike Caught me out a couple of times as well - are you guys twins? You could photothingy your pictures - an eye patch or a parrot on your shoulder would look good. Bren