4 cylinder LPG truck takes lots of cranking to start on a morning, it coughs and runs lumpy but as soon as you touch the accelerator it stalls.

Once its finally got going and warmed up it runs like a swiss watch all day.

Truck had a gas vaporiser 6 months ago due to it leaking and has run fine up to recently.

Its just had a service and new plugs but the fault is still there.

No error codes in the log, could there be a temp sensor faulty thats causing lean mixture when cold or injector fault?

Thanks Andrew