lpg escaping airbox when car off wtf? WTF!!!!!!!! W!!!!T!!!!!!F!!!!!? :/

[slowandlow]

my dual fuel 6 has gotten hard to start, taking about 7 seconds of cranking before it starts. it always used to start near strait away, under 2 seconds cold. it only started happening when my lpg mech. changed the wiring and lpg computer, as it wasnt runing correctly then. after they did that job it was hard to start as i explained above. (i have been asking these guys about this issue, and its been back there to fix, but they r being muppets. no idea whatsoever i think). i located the lpg escaping from my half toasted airbox. my airbox was toasted well before this hard starting problem began, so that isnt the problem i think.
does anyone know if the gas woulda leaked out like this before my problem started, or if the lpg system isnt starting correctly?. or should there not be lpg coming out of the airbox when i turn off? meaning there would be something not working right in the air ductor at the tb...
how long should it take to get lpg from the mixer to the tb? personally i dont think the lpg should be escaping when off, but maybee im wrong.
HELP PLEASE!!!!!

[vk.jonno]

try starting it on petrol mate
then switch to gas, itll work

[slowandlow]

i realise that, but i dont wanna do it that way. ide rather it worked as it did prior. much more betterer...........
thanks for that feedback anyway vkjonno...
would love to hear from someone that knows how lpg systems work

[JMP]

Not sure how yours is set up but mine gets a quick squirt of petrol when I start it and it fires straight away just like it is running on petrol. I don't get any lpg escaping through the airbox though, don't know if any of that helps ya.

[graham7773]

I don't know a lot about lpg systems but I do know this much from sad experience. If you are getting lpg in your air box (I assume air filter box) when your engine is not running, you better hope your ignition is spot on. A back fire will do severe damage to your AFM, airbox and sundry sensors. Saw the results of this on an EF falcon. all the plastic parts of the inlet manifold were destroyed. There should be a complete shutoff of the lpg when you stop your engine. Any lpg leaks are just plain wrong and dangerous. Don't let anybody tell you different. Another point is that when you turn your engine off, the lpg valve is supposed to stop any further gas flowing. the engine spinning down the last few revs should suck any residual gas into the cylinders leaving none in the inlet manifold or airbox. dunno if this helps but I hope so. I thought Holden recommended dual fuel cars starting on petrol then switching to gas?

[slowandlow]

just was hunting around in the passenger footwell and found the lpg computer. its a gastec fp32 fuel processor. from what i can make out so far from net searches, is that this has a petrol start feature too, sounds like the mech hasnt set it up properly. also, anyone know if both the plugs on the FP32 are meant to be in all the time. mine has only one in, and the other is unplugged (i think this one is for the vavle on the pipe taking lpg to the tb. ) it seems to obvious for that to be the issue. i think i need to suss this petrol start feature and maybee question my mech. on that issue.

thanks very much graham and JMP... legends.
any further points of view or additional info will be appreciated. cheers

[slowandlow]

im getting a gut feeling that valve is not connected to the lpg computer when maybee it should be, therefore the valve not operating properly. ill scream if thats it

[graham7773]

start screaming. I think you have hit the nail on the head.

[slowandlow]

well, i still havent confirmed that that isnt the way its meant to run yet as i been in a 20 sleep coma after getting bruised ribs at cricket, but......
WHAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA AAAAAAAAAA!!!!
if that loom is meant to be connected, you can imagine ill have a few choice words to say to the mechanic. how could a qualified lpg installer miss something like that.. i would be expecting some shop credit or something at LEAST. ill post the result anyway...
thanks for the feedback again guys.

[oska]

get it serviced by an LPG service centre ????

[graham7773]

Hey slow, maybe the lpg person you hired was not that qualified?

[slowandlow]

maybee. you would think it would be ok, being a large repco mechanic and lpg installer. i really am wondering whats their deal a.t.m though. seems evertime i go there something new is wrong with the car too. ill talk to them monday anyway. i think i might be going somewhere else from now. noticed a big place on stud rd. on the way to work the other day (LPGAS1). anyone know if they are any good?

[schrinky]

LPGAS1 are one of the best, we have had a system from them installed in my mum's car and have never had an issue, i know its a long way but there is a really good LPG mechanic in Lilydale (Crossmember Automotive Repair) Use to be based in the workshop behind LPGAS1 in Lilydale and did all their dyno tuning for them. We have been going there for years, he always gets the car running well on LPG and has a real nack for finding problems that other mechanics just have not been able to find

[slowandlow]

thanks for the reccommendation schrinky. i took my car back to give the guy 1 more chance. only cos he gave me a loan car for the day (which is almost as much effort to drive as riding a bike. no power steering, a real allround shitebox ). maybee he figuring ill be happy with my car no matter what after driving this, this.... THING for a day or two ..
anyway i was holding my fury in when i spoke to the mechanic today. this is his last chance, so if its not spot on this time ill toss up between lpgas1 or crossmember. the deciding factor will probly be distance. lilydale might be a bit difficult, as i come from dandychong. there an lpgas1 in hallam though which isnt that far really.

p.s. plugging the valve back in didnt really work. mechanics explanation for it being off was, that its ok after its tuned. makes it run in a closed loop or something. i recall reading something like that in the tuning instructions for the fp32, but didnt really understand enough to argue after only reading the thing once.

thanks again for all the feedback. stay tuned for the next installment.....

[slowandlow]

well, i got the car back from them today. they did fix the starting issue by adding the unit that does the fuel injection on start up and the tuning. i really reckon he has redeemed himself here. he wouldnt take any cash for the work. so, parts and probly a good amount of labour time, im really glad i kept my temper and gave him another chance to get it how i wanted. he musta noticed i was holding it all in when i dropped off the car the last time. i was pretty mad . at least he'll get a break from my whinging to him every second day for a while now at least. well, i suppose people will make their own assumption about this garage from this thread, but i think i can at least say the guy is GENUINE in wanting to do the right thing.
thanks guys for all the helpfull info. it really helped me get this sorted out. and thanks to kieth at the garage for fixing my car.