hi guys i have an 03 4.4 lpg converted with an annoying fault she runs perfect on petrol or gas but when run on gas and switched off when restarted she cuts out and will not tickover unless given a little pedal the engine management light comes on but will go off if run on petrol for a while i have had the gas filters done and system checked seems ok any ideas ? lpg system is king lpg

This might seem daft but try unplugging the log ecu & then reconnect it. It solved cutting out problems & engine management light issues. Worth a go as it's quick & easy.

When you say you have had it checked, what do you mean.... it shouldn't put the engine light on and as for not starting that will be down to the inlet manifold full of gas when you start, a little throttle introduces air into the engine and the mixture will drop to an ignitable level.

Sounds like there is a fault with the system or the injectors are in the wrong place in the inlet manifold...

How long has it been doing it??

Has the LPG been plugged into a computer and had the fault codes read and the settings checked?? Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
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my question is,
on you LPG led indicator, is the car restarting on LPG, or on petrol and quickly switching back to LPG assuming car is warm etc. mine (prinz) always does this, (petrol and then LPG) and the led's show it. it is possible to change a setting im told, to force it to start on LPG. like if the petrol tank is compromised.
if its restarting on petrol, is you pump not coming up to pressure?
you could get the LPG serviced, and have it confirmed, (settings)

my old rangie had a switchover method that you had to take revs up to 2000rpm, and it would switchover on the down-rev, never on an up-rev. in case you might be slightly spluttering when pulling across traffic, ie turning right.
my present one doesn't seem to do this, so I guess every make has its differences.

hi thanks for your replies car runs perfect on petrol no engine light starts and runs spot on hot or cold on switching to gas runs perfect switches over after about 1/2 mile. run until hot and switched off on restarting she starts no prob revs go up to around 1000 rpm then drops back and cuts out if i catch revs before she cuts out she will hunt a bit then settle down after a couple of revs she will change to gas and run no probs i changed all the filters air and gas no difference engine light comes on after around 20 miles or soon gas. when run on petrol it will go off after 10/ 20 miles. diagnostics read fault on oxygen sensor left bank which i changed reset system and ran her on gas 20 miles later light came on seemingly a common fault i have had the car around 2 years she started doing this after about 3 months of running. light has been on and off with no apparent damage she is getting around 17/18 mpg on petrol any ideas would be welcome richard

When I had mine I got into the habit of taking it off gas and into petrol a couple of hundred yards from when I stop.
When you restart it does it start on petrol or on gas ?

A couple of things worth checking all your injectors on the gas side is all clean and has not gunned up!

And you have no airlock in the cooling system.

thanks for the reply i have been doing the same taking her off gas before shutting down have not checked injectors yet but will do water system fine no airlock . have not had injectors out any tips ? richard

From what I can remember I would take one of the filters off the lpg, this would be pressurised so where thick gloves to avoid freezer burns. This should depressurise the system up to the injectors, then take them off one by one and clean as you go so you don't loose any bits. Do double check on your manual !
That was what mine was like but I don't know your system!
Mine did it from first install and went back and forth to the installer. I explored all other bits and did the injectors last which ŵas a pain. But in essence it was a brand new system and did not expect the injectors to get ganged up straight away.

hi thanks for that do you think gummed up injector is causing a misfire hence light coming on ? car running well on gas no sign of misfire just this cutting out on start up will have a look at injectors soon thanks richard

Rik

A quick way to clean your injectors is to pur Brake & Clutch cleaner through them, not carb cleaner that will the seals!

I disconnected my filter between the vapouriser & the injectors & filled the pipe to the injectors with fluid, I then re-connected & started the engine, best to have it warmed up ready, when it goes to gas it stutters a bit but if you give it a few revs it will keep going, dont worry if it stalls. I did this 2 or 3 times & all was well no more injector faults showing up & cutting off the gas.

This happened early on in my ownership & a local "LPG Specialist" was suggesting new injectors, it was when i spoke to the guy at Zavoli about injectors that he told me the above to clean them, he also suggested the specialist should have known better.

Since then i have got the software & sorted all my LPG issues myself.

Hope this helps

Neil

thanks that is very helpful will try that richard

The other thing that can cause your symptoms is a small hole in the diaphragm inside the vaporiser, when you switch off the gas gets forced through the vacuum pipe and fills up the inlet manifold, then when you start you have a flooded engine and the car chucking petrol in as well makes it worse, you can tell if it's this by removing the pipe and sniff the end when the engine is turned off... there should be no gas at all down this pipe so any smell and you have problems..

Usually cheaper to just replace the vaporiser if it is this...[/url] Pete

__________________________________________________
2014 L405 Autobiography SDV8 4.4 Loire Blue Ebony interior
2011 L322 Vogue SE 4.4 TDV8 Baltic Blue. Parchment over Navy Interior. Sold
2012 L322 Autobiography 5.0 Supercharged Ipanema Sand, Jet Interior. Sold
2002 L322 Vogue 4.4 V8 Epson Green, Ivory over Aspen Interior (Fatty Offroader) Sold
-Click for Project Fatty off roader-