Airbox exploding

[Timmos]

Is this something that comes as a "feature" with LPG mixer systems?

I've litterally gone through 3 of the things since i converted about 6 months ago. I just had a major service done and i asked the mechanic to adjust the lpg so it wouldn't stall on idle (lpg and hot weather don't work well together) and as i was driving home it blew up again.

Anyone know what causes this?

[alien]

Check the howto section on this forum, there used to be a how to topic on how to use a napisan container's lid to put on your airbox. So when the airbox wants to blow it just shoots the lid off instead of destroying the airbox I think it was for the VS series airboxes, but adapt it to the VY series. That should save you buying airboxes all the time.

[chargedvx6]

Easier still, just bill the installer for the new airbox each time

[moose man]

Replace your spark plugs and leads every year. It's a certain way to stop the backfiring.

[VesperZ]

Yea I had this exact same problem on my VT just after I got my LPG installed. I took it back to him and we went for a drive with some tool to measure the mix of air / gas I think it was. He then noticed there was too much gas when you take your foot off the gas. He then explained to me that he could lean it out, except I would have to modify my driving habits. Basically the way he said it was when you take your foot off the accelerator, directly after you do this it basically doesn't feed any gas through until sometime after. You can kinda notice this through your tacho because it will go down and then sorta come back up. By footing your foot on the accelerator directly after your basically flooding it with gas, so the idea is when you take your foot off the accelerator and waiting a bit it shouldn't back fire. I never had a backfire after that first one so I'm assuming there was some truth to what he explained to me. Also he explained it to me by taking me for a drive and showing the air / gas mixture levels which made much more sense, it's hard to explain things without them showing you. Anyway good luck with it mate.

[colgf]

Just get rid of the gas system , its bad for your engine , sell it on Ebay & run petrol only.

[Timmos]

Just get rid of the gas system , its bad for your engine , sell it on Ebay & run petrol only.

Yep I'm tossing it up.

[GMMAD]

id be checking that all the ignition system is good
backfiring through the intake is usually from bad ignition

[oztech007]

I had the same problem on my vs on lpg.
I drilled a large hole (25mm) in the top of the airbox and then covered it with Duct Tape.
This way if it backfires, it just blasts the tape off.
Saved me lots of Airboxes.

[strgas]

how many kms on your car ? what system is fitted to your car ? where did you have it fitted ? what spark plugs and gap are you running ?

best relief valve for your air box is a simple sink plug , drill a hole into the top of your air box smaller than the plug and attach a wire or chain is supplied with the plug when it back fires it will pop the plug release the pressure and saving your air box then simply refit the plug .

[TMM]

Just get rid of the gas system , its bad for your engine , sell it on Ebay & run petrol only.

This is my opinion too. Not worth it at all unless you do a lot of kilometers.

[strgas]

15 years as a licensed gas fitter i find that most backfires are due to base engine tune and rarely the gas system . Most V6 commodores suffer from poor spark plug lead condition coil packs breaking down vacum leaks , worn valve guides , incorrect spark plugs and gaps , start with the basic's and work from there before blaming the gas system , Think i have had 3 back fires in all the years i have been on gas .