Mopar Muscle Association UK

Mossy68 · Post by **Mossy68** » Mon May 11, 15 9:44 pm

Is anyone on here familiar with Auto LPG ?

Trigger_Andy · Post by **Trigger_Andy** » Mon May 11, 15 10:24 pm

Sexually?

Mossy68 · Post by **Mossy68** » Mon May 11, 15 10:29 pm

Trigger_Andy wrote:Sexually?

no Andy .........

db · Post by db » Mon May 11, 15 10:35 pm

I installed a system on my Sierra 2.8i. Must have been 20 years ago though...

Mossy68 · Post by **Mossy68** » Mon May 11, 15 10:59 pm

db wrote:I installed a system on my Sierra 2.8i. Must have been 20 years ago though...

You'll do then !

When I got my Ram. I knew the LPG wasn't tested. We tried switching it on idle and it ran rough and died. Today I switched whilst driving. It ran perfect until I slowed to idle.
My tease arch suggests that it is sensitive to vacuum leaks etc , amongst other things , so thought I'd check that first.
I found a vacuum pipe from the vaporiser ( which is usually just vented ),which goes to a solenoid ? Then another vacuum pipe off the solenoid which seems to go no where ????
The end seems to have been connected to something but has a split up the side.
I have searched for other pipes and things that it could connect to but can't seem to find anything ???

<img src="" alt="Uploaded with Imgupr">

It's the one that follows the larger pipe to the right

<img src="" alt="Uploaded with Imgupr">

It nearly reaches the brass tube here , but I don't think this is a vacuum connection ?
<img src="" alt="Uploaded with Imgupr">

Mossy68 · Post by **Mossy68** » Mon May 11, 15 11:03 pm

The wires seem to lead here.

<img src="" alt="Uploaded with Imgupr">

db · Post by db » Tue May 12, 15 9:00 am

I'm at a loss mate sorry

Have you looked up the manufacturer?

Pete · Post by **Pete** » Tue May 12, 15 9:06 am

Is that a blind hole in the casting or is it open to atmosphere? If open it would make it run lean at idle.........

Mossy68 · Post by **Mossy68** » Tue May 12, 15 9:34 am

Pete wrote:Is that a blind hole in the casting or is it open to atmosphere? If open it would make it run lean at idle.........

First thing I looked at Pete. Seems to have some sort of grub screw in it.
Sorry. Should have mentioned that.

Carl · Post by **Carl** » Tue May 12, 15 9:53 am

There is a company in Barking that services LPG systems

http://www.biglpg.co.uk/

Dave999 · Post by **Dave999** » Tue May 12, 15 9:59 am

Soulds like an idle cut off solenoid so you don't fill your induction system with gas when the car is stopped

i'd guess its electrically and vaccum controled

igntion on allows the vaporiser to work (electronically controlled)

at low vaccum the idle circuit is off
at high vaccum the idle circuit is on

or some such

and although i can't see the pictures here at work it sounds like the pipe should go to the fitting capped off with the grub screw.

shovelheadrob · Post by **shovelheadrob** » Tue May 12, 15 10:34 am

That is an older vapouriser system, don't know much about that. There is place near Pete W that know all about them, Tilney Tech haven't dealt with them myself but I've heard good things!

Glen63 · Post by **Glen63** » Tue May 12, 15 12:56 pm

It could be a hole in the diagram of the vaporiser, they are prone to wear, which will work under heavy load, but when you drop to idle it cuts supply?

It looks from the picture that you have a small button with a spring on the end of the diaphragm valve on the vaporiser, you may be able to manually work that to see if engine will keep running.

I managed to get a rebuild kit for my vaporiser, but it may be simpler just to buy a new vaporizer, that is normally the only thing that seems to wear on LPG systems.

Be careful you don't cause a backfire of the LPG gas on the intake manifold, my old BMW 2.8i did that a couple of time and blw the Mass Air Flow sensor to pieces both times

My Range Rover has direct injection LPG, which is more complicated thn the old BMW, but does not suffer from that problem. Yours will direct injection as well I assume so you should be safe.

Mossy68 · Post by **Mossy68** » Tue May 12, 15 6:36 pm

Thanks for your replies gents.
May have to take it to a local place and get it looked at.
I was with Daves way of thinking. Some sort of pressure control thing.
I'm not going to guess where the pipe might go. Don't fancy a KABOOOOOOOM !!!!!
I'll keep looking for info in the meantime.