Hi, I have an EL with the factory tickford gas system from vialle. It runs perfectly in the driveway but everytime I take it for a drive it stalls when I try to slow down. I have checked the stepper, the diaphrams in the converter, have reset the ams. Ford won't tell me anything about the system and the local gas shops are falling over themselves to charge me $1,000 to fit a new converter but when queried about the nature of the problem seem to be clueless. Any advice would be welcome.

Check the balance tube for leaks , even pin holes can cause problems. Next the idle solenoid valve could need a clean.

Mine had the same problem, turned out the air intake manifold was cracked along the seam due to a back fire, so the air mix was obviously wrong. same symptoms as yours but i dont know wether its the same problem. Good luck mate

i here this balancer line thing being used as the excuse for everything.....is that the tube that runs from the convertor to the airbox? I am running without an airbox, just straight into the mixer and ive noticed sweet f**k all difference.....

yeah youd want to be checking for vacume leaks in the entire intake system (including manifold to head bolts)....maybe u can bump the idle up a little and also check the ring hasnt become dislodged in the rubber elbow....

after these and other basic checks such as ignition i would only then look at the converter

I forgot to mention that the car runs perfectly on petrol. Are there any problems that will affect the lpg like this but won't show up when using petrol.

Clean your idle jet out, its under a solenoid on top of the converter. You will need some long fine wire to reach inside to unblock it.

Thanks for the tip, I have just tried this and still no difference. Any other ideas?

I have a similar problem with a NL Fairlane 4.0i dual fuel I purchased recently.
There is a small white bakelite bit that sits under the stepper motor (I think thats what it is called). It has a tube that runs back into the rocker cover.
Mine was installed backwards and as such had snapped the little hose attachment part.
I visited Gas Power Australia (Coiuldnt even tell me what the part was or what it did. Very dissapointed with the service recieved) went to Steens who actually installed the system in 2000 and they said they didn't know what the broken part was and I should just remove it???
Titan Ford even argued with me that it shouldn't even be there. Until one of their older guys said something about it being a tickford fitted part to get more air in at Idle as all the Ef/EL/AU's had the same stalling problems.
Eventually a Gas place in Midland was able to tell me what it is/does and thus to fix the problem.

The part that you are refering to is to shift the PCV hose from the inlet manifold between cyl 3 and 4 to below the idle control solinoid so each cyl get an equal LPG mixture. All it does is to improve the idle.

b r Check the balance hose for leaks

replace the converter with an OMVL