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Being really really miserly and mean, and since I have already had the family's Fiat Punto successfully converted to LPG (liquefied petroleum gas) which is 50% of the price of petrol (="gas") over here in the UK, I am wondering if anyone here has converted and Insight to LPG, and if so, what the outcome was?

Grateful for any information.
 

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I'm considering it too. The space under the "hidden storage" in the boot looks big enough for a tank but it's a weird shape so the usual "spare tyre replacement" tank wouldn't fit there. A stubby cylinder might.
 

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LPG Conversion on 2010 model

I am picking up a 2010 insight tomorrow and see it as a car to see me into retirement next year. Economy therefore is paramount. I have previously had two cars (Peugeot 406 and a Renault Scenic) converted to LPG and was very pleased with the economics when keeping the car for three years or more (which I intend to do with this one - as long as it will run as far as I am concerned)

Has anyone on here ever had one of these converted (probably addressing mostly UK users as fuel is a lot cheaper in the US) I can see there might be space issues for the tank, as there is no spare wheel to remove and it will have to sit in the boot (presumably making the battery inaccessible without removing the tank - is access to the battery needed in normal use/servicing?) I can live with losing some of the space in the boot as with only two of us we can just fold the back seat down when extra space is needed.

I would be interested to hear from anyone who has done this already, and maybe see some pics of your installation - also hear from anyone who considered and then rejected it and why. I understand the economics of it but have no doubt I would recover the installation costs in less than three years as well as making the car a little more environmentally friendly too. Allowing for the slight performance hit i have always found LPG saved me around 40-45% on my fuel costs once the cost of installation was recovered

I am more concerned with the feasibility of doing this and whether it might have any impact on a hybrid which I have no experience of previously. I am guessing it might throw out readings on economy but again that is something I could live with.
 

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Has anyone followed up on this yet

I will certainly take a look at the space mentioned here - there are quite a few tank types around now
 

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Ive seen off road only kits for 4 and 6 cylinder vehicles. The problem is the engine is off half the time so we would need a solonoid on/off valve tied to the injector signal. Other than a possible dtc from no fuel psi if you can mount the cylinder, plumb it and regulate it :), it sounds possible.

The gen 2 is drive by wire, no throttle cable, but I am sure something could be rigged up.
 

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You'll struggle with stop-start and accurate fuel metering at low loads.

LPG systems play a "man in the middle" attack on the petrol fuel injectors. "What pulsewidth (on petrol) is the petrol ECU commanding?" "What is this equivalent to in LPG?" "Fire the LPG injector for that amount of time."

As a result they always lag the petrol injections, sometimes by one cylinder, sometimes by one complete revolution. (better Polish and Dutch systems allow you to choose, cheap Italian systems don't...) This wreaks havoc with stop-start, and the ultra-fast IMA style stop-start will make it worse.

Low load metering is tricky with LPG systems. With no scientific "calibration curve" for what injector opening time = what quantity of fuel injected, on either petrol or LPG, you've got to "fudge it" manually on each vehicle by guesswork/watching oxygen sensor readings and so forth. Easy on a dirty great inefficient low revving V8. Much harder on engines with a wide operating range (low idle/high redline, and/or forced induction. The Insight would be very tricky as the fuel injected during lean burn is de-minimus, yet it's this low-load operating point that's most important for fuel economy. Most installers just set the thing to run rich and hope that the drivers, knowing that their big ol' V8 now costs nothing to run, then hoon it around everywhere and don't spend much time at low load. In an Insight driven for economy you'd have the opposite situation.

Timing: I don't know of ANY LPG system that offers sub 0.1msec injection timing accuracy. (they can do 2.0, 2.1, or 2.2msec, but not say 2.12msec) They just aren't built for accurate fuel metering at low load because when fuel is cheap who cares, right? The Insight most definitely uses sub 0.1msec injection timing resolution. You'll get "dirty great gob of fuel" or "nothing at all" and the petrol ECU won't like that.

Payback: Have you done the sums? Have you factored in the lower calorific value of LPG, the additional maintenance costs, and the scheduled price rises courtesy of duty increases to bring LPG taxation into line with petrol/diesel? An LPG conversion won't pay for itself on an Insight unless you're going to do >200k in the next 5 years. Planning on being a cabbie? ;)
 

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I know they use this with diesels to add MORE POWER. What if this was on constantly to supplement the fuel? Would the o2 sensor roll back the fuel or gasoline used if this was on a constant drip?

Yeah, I use to work near a cng pump and knew the owner. He offered me the ability to fill up if I had a conversion, but the sets were exactly as you described. Very rich and mostly unregulated.
 

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Different animals.

Toyota's hybrid system doesn't operate the engine at low load. It's either on and running at peak efficiency, which is quite a high load, or off.

You've still got stop-start, but as it's only a transient scenario the idle tuning is way less important (make it rich and forget about it won't materially affect economy) and this makes for a much easier conversion.
 
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