I would like to know how to force my car to start on LPG whenever i want to. It is duel fuel non-factory, and the converter is made by Airod.

Currently, if the car is run on LPG without the switch being turned to petrol, the car will start on LPG. But if the car is run on petrol and then the engine is stopped and then you switch to LPG, it will start on petrol and switch to LPG at around 1200rpm.

If the kit is a full air rod kit and the switch that you have in the console has a little black button in the centre, if you hold that button for a count of 15 sec it will then select the LPG yellow light and allow you to start it on gas only. Usually after you have switched the engine off the little red petrol light will stay lit meaning it will start on petrol and the orange light flashing waiting for it to change over to gas and by holding the button will enable to be started on gas assuming it is the MED switch.

Thanks
Joe

Thanks heaps, i'll try that.

Unfortunately i made a mistake in my first post. The car actually starts on petrol every time regardless of what has happenned previously.

Even more unfortunate is that today i did some testing on LPG and didn't pay enough attention to the fact my petrol guage was very low. The car stalled a few times on LPG, then i couldn't start the car despite having heaps of LPG because i had run out of petrol (A couple of days ago i did a number of full throttle testing runs on petrol and gee it sucked it's way through a lot of it, caught me out).

have you had the mixtures checked asuming that every thing else is right.

I have tried the lpg only start and it worked excellently. After holding the switching button for 6 seconds the orange light stays on and then after a few cranks it starts fine on LPG.

As for the mixtures, i have just had an adjustment screw pointed out to me on my Airod, it has a + and - next to it. I previously learnt how to tune my OMVL, so maybe i can tune this myself as well? I take it the + and - screw is the mixture, while the knurled knob is the idle speed? Then again, one is normally called the "sensitivity" isn't it?

the +...... - screw which is resessed in the convertor is the sensitivity screw & the other one on the top is the mixture screw, screw the mixture all the way in & get it to run on the sensitivity screw then turn the sensitivity screw in lean so the engine just start to run rough then adjust the mixture screw so the engine smoothen out....... be carefull with the mixture screw as its very sensitive to change......meaning 1/4 of a turn may show a 2.0% change on C.O a gas anyilzer would be highy recomended to get it right, after all this is done & you may or may not experiance a slight hesitation on take of a very sight turn of the sensitivity screw out rich will fix the hesitaion but then you have to readjust the mixture as it will have effected it as well.......
hope this helps...

Joe

This helps, thanks. It's good to know which is which (my bypass brass knurled knob is on the side, opposite to the sensitivity screw). Thankfully you describe the same basic tuning process i used on my OMVL.

Except you don't mention disconnecting the ISC and using a 0.75mm feeler guage between the throttle stop? When i did this previously on my XG it gave a rather high idle, i could have used a thinner guage and the engine would still have run. In fact it ran with no guage from memory, but only just. I suspect the AU in the EB will need some guage though.

I asuumed that, that side was right, but set the throtle base idle as per normal for petrol, then set the gas mixtures to suit, the only time I worry about the base idle is if I know there is a problem, I dont use a feeler gauge to set base idle, I set it for what the engine needs to many other factors that may play havock in trying to set it with feeler gauges.......

Joe

My impression was you disconnect the ISC so it doesn't adjust itself while you are trying to adjust the lpg mixtures, and use a feeler guage to make the engine idle rather than stall or be unable to start?

This afternoon i used a 0.75mm guage at first and set the mixtures up nice, but when i reconnected the ISC and removed the guage the engine stalled and wouldn't start. A 0.40mm guage got me closer, but i wonder if you really should just tune the idle so it can start, if you want it to be able to start on lpg that is?

Even so, i don't think i'm going to get it to work the way it is. I can set it up nice and it does everything nice, except when i brake the engine stalls. I tried upping the sensitivity screw and this helped, but even so it still stalled when braking.

I also got another problem where if i let the car coast and then pressed the accelerator pedal, nothing would happen for about 2 to 3 seconds. I don't know if that might be a result of too much sensitivity screw? The sesitivity screw was by then richer than required to start and run the motor, and the bypass was all the way in, by then the motor was a fair way off needing the bypass to idle nice.

So i don't see a solution in the tuning. I need to work out why it is stalling under braking, as well as the other problem of the injectors letting heaps of petrol in while running on lpg.

Curse lpg.

ok, fix all of your fuel problems first then sort the gas out....

I did all of the testing mentioned above with the injectors disconnected, so the stalling under braking problem was purely with the lpg. As mentioned i tried to compensate for the stalling under braking by upping the sensitivity, but this didn't solve the problem and introduced others.

My best guess as to why the stalling is happenning, is because the mixer being at the beginning of the crosspipe is too far from the intake ports and coupled with the vacuum consumed by the brake booster there is insufficient suck from the motor under idle and braking to keep the converter operational, and it is shutting down. That is my best guess.

Thanks for your help so far Joe. Much appreciated.

Whether i need it or not i have decided to get an e-gas mixer/throttle body, so i will fit that and see how things go.