my dad has an ef falcon on lpg he reconed the motor 50 thousand ago recently it stated to run rough and would chase idle in dive then it back fired one day and it all went down hill from there it was then running realy rough and making a clacking noise witch got a bit better when it cooled but would start up again when the heat built up i pulled the leads to check for spark they were all good but the engine only ran rougher when i removed the first 3 leads there was no change on 4,5,6 we did the coil pack and no change its the same petrol or gas and i checked the timing with the car in base mode and it was retarded badly but i have only ever owned el falcons with a dizzy so i have no idear if thats right or how the ef timing works could it be the cam angle sensor sending the wrong signal we noticed there was some slack on the timming chain on the oposite side from the tensioner could it have been to tight and failed any way the old man cracked the s**t and took it to a mechanic he removed the head reconed he found intake piping chunks in barrel 6 removed them charged him $1300 he left and it ran fine he got 100 kms away it back fired and it all started again he towed it back now the guy recons he cant fix it he has no idear whats wrong and he thinks he found metal fillings in the rocker cover am i missing something here or is this all just dumb well this is every thing i know about it from what i could understand from the old mans jibber jabber and what i had time to check. i replaced the spark plugs too. he could have just chucked a new engine in for that kind of cash

did you see his busnesis name?
i wasn't "dogdey autos" or "rip off mechcanics"
you could check your vac hoses as these are prone to falling off after a backfire and giving some of the symptons your showing
but i feel it's something more sinster
has anyone played with the round thingy where the dissy normally goes?
you can adjust this but i've never done it so don't ask me how

Timing is 100% ecu controlled.

I would be looking to see if the balancer has moved.

we replaced the balancer too, there was no change