I'm about to LPG my 100Series '98 model Cruiser and have been told that the ECU is tool old to get the benefits of vapour injection LPG and should just go with the the old fashioned venturi system. Anyone have any opinions on either ?
Cheers,





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I run the Eurogas vapour injection on my 95 80 series and have not had any of these issuescarts wrote:Stop press:
I am still in the process of sorting out some issues relating to LPG injection on my 97 model 80.
I am running a KME Diego system and there are a few idiosyncrasies to do with 80 series computers that is being rater problematic. All of the vapour injection lpg systems get their fuel delivery information straight from the injector pulse that the factory ECU puts out. It seems that the 80 does a strange thing. When the TPS is at idle, the injector pulse is say 4.3ms. When you just crack open the throttle a tiny amount, just enough to come off the idle validation switch, the actual injector pulse drops to say around 3.8ms and you can hear an audible click coming from something attached to the fuel rail. The long and short of it is, the drop in injector pulse can be felt on lpg as a flat spot, whereas, whatever the click is on petrol to do with possible increase in fuel rail pressure, means that no hesitation can be felt on petrol. This problem is something you can't remove completely on gas as the software isn't intuitive enough to have infinite adjustment at low rpm. We can tune it well enough though so that 95% of people wouldn't even notice.
The 2nd problem is, when the vehicle is cool, say 10 minutes after startup, gas rail pressure is regulated at 1.45bar and as the car heats up, particularly at idle in traffic and offroad, gas rail pressure is dropping to 1.28-1.30 bar, which gives a noticeable rougher idle and leaning out fuel mixture which can be felt as a loss of power. We have replaced the the regulator valve in the mixer, but it is still giving the same symptoms. The problem is however, if the later 80 series ran a closed loop system like the earlier 80's, you wouldnt have a problem with the leaning out, bcause the O2 sensor would just increase fuel delivery.
Basically, the long and short of it is, without the closed loop setup, there are some annoying variables in the lpg system that the factory computer will not see and will not be able to compensate for.
We are still not giving up yet. We will probably still replace the convertor unit, drill out the nozzles to a larger size and reduce the regulated rail pressure to see if that will improve the situation.
If the 100 4.5 engine management is similar to that of the late 80 series, then look out. These ECU's are as intelligent as you would hope in open loop mode.
is yours the update 80 series without the o2 sensor? or is it still on the changeover and run the flap type air flow meter?zackde wrote:I run the Eurogas vapour injection on my 95 80 series and have not had any of these issuescarts wrote:Stop press:
I am still in the process of sorting out some issues relating to LPG injection on my 97 model 80.
I am running a KME Diego system and there are a few idiosyncrasies to do with 80 series computers that is being rater problematic. All of the vapour injection lpg systems get their fuel delivery information straight from the injector pulse that the factory ECU puts out. It seems that the 80 does a strange thing. When the TPS is at idle, the injector pulse is say 4.3ms. When you just crack open the throttle a tiny amount, just enough to come off the idle validation switch, the actual injector pulse drops to say around 3.8ms and you can hear an audible click coming from something attached to the fuel rail. The long and short of it is, the drop in injector pulse can be felt on lpg as a flat spot, whereas, whatever the click is on petrol to do with possible increase in fuel rail pressure, means that no hesitation can be felt on petrol. This problem is something you can't remove completely on gas as the software isn't intuitive enough to have infinite adjustment at low rpm. We can tune it well enough though so that 95% of people wouldn't even notice.
The 2nd problem is, when the vehicle is cool, say 10 minutes after startup, gas rail pressure is regulated at 1.45bar and as the car heats up, particularly at idle in traffic and offroad, gas rail pressure is dropping to 1.28-1.30 bar, which gives a noticeable rougher idle and leaning out fuel mixture which can be felt as a loss of power. We have replaced the the regulator valve in the mixer, but it is still giving the same symptoms. The problem is however, if the later 80 series ran a closed loop system like the earlier 80's, you wouldnt have a problem with the leaning out, bcause the O2 sensor would just increase fuel delivery.
Basically, the long and short of it is, without the closed loop setup, there are some annoying variables in the lpg system that the factory computer will not see and will not be able to compensate for.
We are still not giving up yet. We will probably still replace the convertor unit, drill out the nozzles to a larger size and reduce the regulated rail pressure to see if that will improve the situation.
If the 100 4.5 engine management is similar to that of the late 80 series, then look out. These ECU's are as intelligent as you would hope in open loop mode.
Mine is an update model with the O2.carts wrote:is yours the update 80 series without the o2 sensor? or is it still on the changeover and run the flap type air flow meter?zackde wrote:I run the Eurogas vapour injection on my 95 80 series and have not had any of these issuescarts wrote:Stop press:
I am still in the process of sorting out some issues relating to LPG injection on my 97 model 80.
I am running a KME Diego system and there are a few idiosyncrasies to do with 80 series computers that is being rater problematic. All of the vapour injection lpg systems get their fuel delivery information straight from the injector pulse that the factory ECU puts out. It seems that the 80 does a strange thing. When the TPS is at idle, the injector pulse is say 4.3ms. When you just crack open the throttle a tiny amount, just enough to come off the idle validation switch, the actual injector pulse drops to say around 3.8ms and you can hear an audible click coming from something attached to the fuel rail. The long and short of it is, the drop in injector pulse can be felt on lpg as a flat spot, whereas, whatever the click is on petrol to do with possible increase in fuel rail pressure, means that no hesitation can be felt on petrol. This problem is something you can't remove completely on gas as the software isn't intuitive enough to have infinite adjustment at low rpm. We can tune it well enough though so that 95% of people wouldn't even notice.
The 2nd problem is, when the vehicle is cool, say 10 minutes after startup, gas rail pressure is regulated at 1.45bar and as the car heats up, particularly at idle in traffic and offroad, gas rail pressure is dropping to 1.28-1.30 bar, which gives a noticeable rougher idle and leaning out fuel mixture which can be felt as a loss of power. We have replaced the the regulator valve in the mixer, but it is still giving the same symptoms. The problem is however, if the later 80 series ran a closed loop system like the earlier 80's, you wouldnt have a problem with the leaning out, bcause the O2 sensor would just increase fuel delivery.
Basically, the long and short of it is, without the closed loop setup, there are some annoying variables in the lpg system that the factory computer will not see and will not be able to compensate for.
We are still not giving up yet. We will probably still replace the convertor unit, drill out the nozzles to a larger size and reduce the regulated rail pressure to see if that will improve the situation.
If the 100 4.5 engine management is similar to that of the late 80 series, then look out. These ECU's are as intelligent as you would hope in open loop mode.
either way, we are still in the troubleshooting phase, and it is no means an indication of the quality of the kme system. as far as power and economy go, power difference is unnoticable and fuel consumption is only marginally worse. There may well be a fault in the convertor and the problem associated with the drop in injector pulse may be a crook TPS which is unnoticable running on petrol.
The fact still remains though, without an O2 sensor running a closed loop system, any variables in gas delivery will not be seen by the factory ECU, therefore it is not intuitive enough to deal with it.
It is the programming in the factory computer that prevents you from using an O2 sensor. Pre 95 model 1FZFE's computers ran a closed loop system. You have an O2 sensor in your exhaust. Post 95 model computers run an open loop system where there is no option to simply "run" an O2 sensor. They dont offer the functionality.the_quokka wrote:Am I missing something here ? What is preventing you using an O2 sensor ?
If it is still running an O2 sensor, then it is still running the earlier closed loop injection system, which explains why you are having no issues with your SVI.zackde wrote:
Mine is an update model with the O2.
The system I've been looking at is the Landi Renzo. On their web site they say "The LPG ECU is able to calculate LPG injection timing using specific information as LPG injector rail pressure, LPG temperature, engine coolant temperature, engine RPM and battery voltage, in addition to the inputs of the gasoline ECU. Completely self calibrating using model based algorithms"carts wrote: As said before though, you would want to have a very stable gas pressure on your rails, as the variables present in the gas system can influence the running of your car considerably, and without a closed loop system, the car will never know its running rich or lean.
So was your install the injection ? And which year/model Cruiser are you running ?the_quokka wrote:My vehicle's economy is unmistakenably improving progressively, now on it's fourth fill. It is one of the other Italian topline makes ...
But you still have to be ever so careful. I walked into one shop who was doing OMVL and I asked them about the model of convertor they were installing and they mumbled some sort of Bulgarian make to me.
Already provided in the first response to this thread. In case the "convertor" threw your faith - you still have to have a convertor in order to provide a consistent pressure to the LPG Injectors ... Ok that's not quite the right terminology in all cases - in my other SVI Italian system - it vaporises via a thermal jacket before it gets to a special pressure valve + filter. The point I was making is ask a few probing questions on this stuff. e.g. especially for an 80 - how close will the exhaust be to the fitted tank - what will you do about it ? If you get treated like a mushroom - well, trust me, light up a torch and run away, it will reduce your chances of gross spore developments in the futurepiperchau wrote:So was your install the injection ? And which year/model Cruiser are you running ?the_quokka wrote:My vehicle's economy is unmistakenably improving progressively, now on it's fourth fill. It is one of the other Italian topline makes ...
But you still have to be ever so careful. I walked into one shop who was doing OMVL and I asked them about the model of convertor they were installing and they mumbled some sort of Bulgarian make to me.
Thanks,
Mark
sorry can't help there - far different make + ECU and I have no equipment anyway. Around town I am getting a lot less than the 400+ I stated before which was a majority country run ....I have an auto + standard tyres and height ..... lot of factors affect fuel economy. You can also be hoodwinked by these stupid quick shut off valves they are introducing at some servos too. Mine seems to idle a little quicker so I guess it's running richer at low revs .... but that is all I can tell ... certainly doesn't hold back when you put the boot in - especially ECT. goes well.dazlin wrote:question for "the_quokka".
do you have a copy or an image of your gas mapping?
i just recently put gas injection on my 98 100 series 4.5 manual and am struggling to get 300k out of a 90l tank. the guys have changed the gas mapping several times and tuned it on the dyno. I use to get 380k on petrol from 80l. The cruiser is on 35" muddies and has bull bar work so it weighs a lot but i would have thought that gas injection would get me the same sort of k' compared to petrol +/- 5% as thats what everyone has told me. I am interesting in seeing what sort of gas injection mapping others run in comparison to mine. The system i have installed is EuroGas.
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