VS ute stalling on fuel but not on gas ?

[Elise21]

Hi,
I have a 1996 VS ute on duel fuel and it has had problems running on fuel for some time now.
The last time it played up it was being driven on fuel the car was turned off and then would not start again which ended up draining the battery...the gas system had to be hotwired so that it would start straight on gas...which worked.
I had the fuel pump replaced and thought that my problem was solved as it has not had any issues starting on petrol before switching itself to gas since...however, when coming home tonight i was running low on gas so decided to flick it over to petrol...it was fine until I had to come to a halt at the roundabout, i then went to take off and the car stalled...I turned the car off tried to start it twice and it didnt even attempt to turn over, I put the car into park, it started and switched itself over to gas, and away I went...

It will run fine on fuel if you are travelling on the highway for example but every time it has stalled on me it has been after taking off from traffic lights etc..

[The1]

fuel pressure regulator maybe?

[Elise21]

Ok...I spoke to my mechanic this morning and he thinks that its just because the car doesnt get run on fuel enough and therefore, the injectors would be dry, but that doesn't really make sense to me because its fine if you are moving, and its also fine if you just sit it in park and have it idle on petrol.
Is it likely that it could be because it doesnt get driven on fuel enough ?

[The1]

i doubt it, try pulling the vacumme off the fuel regulator and see if fuel comes out there, there shouldn't be any.

[Elise21]

Ok but can you tell me where that is and what it looks like...sorry to be a pain

[The1]

sorry mate, it's at the back of the engine on the fuel rail.

[bpefi]

You should use at least 20 litres per fortnight by driving on petrol - as the petrol circulates all the time - this leads to buildup of heat & gum's up injectors & stuff like that. If its not a genuine LPG system - you need to fit a genuine petrol / Lpg dual map tune - this will allow it to start on petrol & switch the fuel pump off on LPG. It will improve starting out of sight - power & fuel economy. For power on LPG & petrol throw the mixer ring away & fit a Blos variable mixer off Ebay - then your car will drive like its on petrol std. You Lose 30% of power with std mixer ring. Fit some Pulstar plugs & you wont get backfiring - pick up fuel economy & power as well.

[Elise21]

The car is fitted with a proper gas system, every time it starts itself on petrol and then switches itself over to gas...and the fuel pressure regulator is not the problem...any other ideas on what could be causing the stalling ??

[bpefi]

You stated that it wouldn't crank over - you put it into park & it then cranked & started - if its not cranking in neutral & does in park then it could be as simple as a neutral switch - in a VS I do not know what it uses - so it might be a problem with a switch that tells it where it is.

[bpefi]

You say the LPG had to be hotwired ?? Can you be more specific here please - exactly what did you hot wire..???

[Elise21]

On the passenger side of the engine bay is where all the gas gear is, im not exactly sure how it was done but a wire was placed on something before cranking the car over which tricked the system into starting straight on gas instead of petrol first. The only problem I am having now is that I cant drive it on fuel because when I come to a halt and go to take off the car stalls, it has no problem starting itself on petrol and driving on gas.

[bpefi]

On the passenger side of the engine bay is where all the gas gear is, im not exactly sure how it was done but a wire was placed on something before cranking the car over which tricked the system into starting straight on gas instead of petrol first. The only problem I am having now is that I cant drive it on fuel because when I come to a halt and go to take off the car stalls, it has no problem starting itself on petrol and driving on gas.

Ok - so what is the part that makes it start on petrol - part # & brand ?? Most start on both at the same time & then switch petrol off once its started as it takes time for the LPG to come up & be enough to keep it going.

[Elise21]

Im not sure what brand it is but I dont think that the LPG system is the problem as it was only fitted a few months back and it was still stalling on petrol on the old system (manual switch to change from petrol to gas)

[bpefi]

Sorry but you need to answer questions & be a bit more explicit for us to help - we need every bit of information to do anything I have asked three questions & got nothing - you need to be clear in your response - like why hot wire the lpg. Most systems start on both fuels then switch the gas off??? I asked what type of gas components & you cant or wont tell me - if you cant provide what we need then no one is going to help ... simple as that...

[Elise21]

Sorry im a chick so dont know where to find the things u ask....just thought people may have ideas on why its stalling on fuel when u come to a halt, so that I dont have to waste as much time at the mechanics...but not to worry!!

[bpefi]

Well maybe you have someone around that can help you - to identify the LPG parts - there is always something written on them - just look closely & write it all down.

On petrol you can have the injectors cleaned on car or off car - throttle bodies need cleaning every so often - both will help idle. The computer controls the idle speed itself - so maybe just disconnecting the battery for 30 minutes can help. Once you reconnect it you will have to reteach it so it has some memory of what is right. So basically you have to get it warm & then let it idle for 4 minutes in & out of gear with ac on & off.

If you want power & fuel economy on LPG I can help - I would be going with the genuine dual map memcal - then the computer controls everything - you then have the correct timing for LPG - it made a huge impact on the way ours runs - starts perfectly every time.

The other thing you can do - depending on What LPG converter that you have is fit a BLOS mixer off Ebay - std mixer restricts air flow badly - this is what they call a variable mixer - power will be similar to petrol operation.