hiya.. just looking for opinions/ideas..
after months of tune issues with dual fuel idle problem; problem mostly with petrol: rough, erratic idle, throttle sticking after downshift; flat take off/low revs, and a bit of jerkiness at steady revs, the lpg finally gave up and started running worse than petrol; undrivable; no power, very rough idle...
took it to mechanic finally for a major service/tune up but couldn't fix all probs; but he did learn that the issues are NOT fuel related ie pumps or sensors etc; NOT ignition: new plugs, leads, dissie inspected and electronic parts replaced; throttle body and cable fine.... basically was traced to timing/tune and PROBABLY idle control valve...which is mechanically sound, bout probably electrically buggerd...lpg prob turned out to be faulty mixture controller (or whatever they are called..)in the line between the mixer and throttle body, managed by lpg computer..
point is: i.c. valve now unpluged; car runs great. not perfect, but cam regrind, extractors and exhaust make the car sound rough (in a good way!!); also, mechanic failed to notice map sensor unhooked after he backfired it, which made it much worse til i plugged it back in!!!
with a plug change and retune today, manually advanced timing and NO idle control valve (and a mechanical/spring screw lpg mix controller), the car is running as good as it's ever been........
my main qusetion is of course is: do i have to get a new i.c.valve??? is it essential? what can go wrong without it?? what if i clean it again, put it back on, leave it unplugged......? whats the worst that can happen?? how can i make so i don't need one at all??
i only ask cos i'm kinda broke, and the $175 for a new one (repco) could be better spent elsewhere..

i saw that some person on this forum ended up just putting a piece of gasket paper that hasnt been cut to cover over the holes.. rendering it useless pretty much. he said it ran great

thays kinda what i'm hoping for... or just give it a really good clean so any air that goes thru it is not restricted or hindered..is that what they do? increas/decrease air mix depending on what the computer thinks it needs at any given rpm????
but yeah..i'm thinkin get rid of it and cover the hole... but wouldn't that send an error code to the ecu if it's unplugged??? what would the ecu do to compensate..?

im pretty sure that he left it plugged in..

im pretty sure the ISC only comes into play when the car is idling, alowing air flow through the ISC into the TB without having to open up the butterfly hinge..

when i did the base idle reset, i adjusted the idle screw until i got it to where i was happy.. and it idled fine without the ISC plugged in.. i didnt really notice a difference to be honest.

bit of an update... this morning with cold start, car not so happy..... looks like the new isc has to be bought.. will try wrecker first and give a modified gasket a go.....