Calling all LPG owners...

[Hedders]

philoldsmobile said:

Hedders said:

matt21 said:

more news.

About 1/2 a mile from work it switched to gas all ok. Then I got to a junction pulled out and it stuttered and cut out. Eventually it stuttered back into life and was fine! Airlock?!

Now on 300 miles and the low gas light is on. Sounds about right I guess. I will fill up tomorrow and see if I can get any in.

Not having much luck so far!

When the LPG is running low (in my car atleast) you should notice that the car will just not accelerate with any gusto.

When it is really empty, it will stutter and even 'backfire' (blew my mates airfilter housing to pieces in his VW Jetta).

So far, i am loving cruising on gas

unless its a very basic system, there is likely a pressure sensor that is either incorrectly calibrated, or not fitted.

I think it is a very basic system installed on a budget by the PO. I will pop into an gas convertion place and see what they think though.

[philoldsmobile]

it may be possible to get a low pressure valve installed, but i dont know for sure. it may depend on what sort of system is installed.

there is some very good info on this link. a basic system may not support a low pressure switch.

http://www.v8dualfuel.com/lpg_information/solenoid...

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from v8dualfuel.com


Electronic controlled main flow adjusters (exclusively for later Efi type applications)

With input from the lamda probe in the exhaust providing a voltage signal output relevant to weak or rich emissions, and throttle potentiometer (throttle positon information) relating to full throttle power requirement or part throttle cruise (plus all variants between) combine to activate a stepper moter that enables futher control of LPG delivery between the vaporizor and LPG mixer for optimum economy. This system is supplied with all Hot-wire and Gems type Rover Efi sytems included. An additional supply of separate lambda probes if required is available and recommended. The Software system we use (Millennium/Leonardo) also offers unique advantages with the ability of self-learning, and can further minimise fuel consumption and power losses compared with other manual, fixed main-flow adjusters (see below) or lesser lambda-controlled systems.

The LPG peak flow controller/solenoid (stepper) receives its information from the Lambda sensor and throttle position sensor to compensate for and adust to relevant fuel flow requiments, both for cruise passsive driving and the more demanding load pulling or hurried accelaration times.

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in essence, there are two ways the system can switch to petrol, 1st if the fuel pressure drops below a prescribed level, or secondly if the 02 sensor detects a lean condition (i.e. insufficient fuel pressure) meaning it goes outside of its permissible value, therefore defaulting to petrol.

Edited by philoldsmobile on Sunday 2nd May 13:38

[Hedders]

Cheers,

I will make a note of what parts are actually installed in my car, and make some enquiries

[matt21]

I have changed the plugs with NGK platinum and must concede it does drive better.

However, it still misses soon after changes over to gas and still get the engine emissions light on and a rough idle.

What shall I do, and what could be causing it??

[Foie Gras]

Thanks guys - great thread, in 15 mins I've managed to get a basic understanding and quell some fears.

I bought an F150 Lightning yesterday that had LPG fitted. It looked like it had a full tank when I drove it away but I lost any real acceleration about 140 miles down the road. The lpg gauge on the dash then started beeping and the engine switched to petrol.

When I went to the garage, it wouldn't take any lpg and the gauge was still showing full. Next garage, same problem even though it seemed that I had a good seal and lock both times.

Reading this now makes me strongly suspect pressure valve/solenoid problems.

Anyone know how much it costs (roughly) to fix these. The dealer would willingly fix them, but they are now 200 miles away and if it's a £50 job, I'll pay for it myself and get it done locally.

Cheers



FG

[ABIL]

Hi Guys,

I have a L322 RR with OMVL LPG system fitted. Trying to fill the gas at 2 different stations but it is not letting me fill in. It only goes up to where the Pump meter goes to 0.00...THEN it does not move any further or start to fill the gas. Even though I have recently bought the car, but have managed to fill the gas at few occasions myself, so this time I could not. At first station I though may be I am not doing something correct so I called the staff to help and guide but it seems I was doing correctly putting the nozzle...clicking and so..Any ideas what it could be....seems like a air lock to me.....but not sure how to rectify? Would appreciate any feed back guys and thanks in advance.....

[V8 FOU]

You often have to wait for the pump to start for anything up to 5 mins - especially in the colder weather. Just keep the button pressed and wait! Tends to be worse if the pump hasn't been used for some time.

[andrewrob]

V8 FOU said:

You often have to wait for the pump to start for anything up to 5 mins - especially in the colder weather. Just keep the button pressed and wait! Tends to be worse if the pump hasn't been used for some time.

I've never had to wait more than 10 seconds for it to start putting gas in, regardless of weather. Are you sure its not just the person behind the counter not hitting the button for a bit?

[schmooveboy]

Going to bump this as I was having some problems this morning.

Any acceleration in my E38 728 harsh enough for a gear change caused the LPG system to switch off and switch back to petrol. I am thinking this would be a low pressure issue (tank is full) or perhaps a blocked filter but I am not sure.

It makes a beep when each injector is running on start up and there is always a longer pause between 1 and 2 so maybe number 2 has a tough start up for some reason. I thought it was just fuel surging around the tank but with a full tank as it is now that isn't really relevant.

It has done this sporadically since I bought it a couple of months ago. The LPG system was installed in Poland by the previous owner so I have no idea what system it is sadly. Last night it took 20 miles for the system to kick in. Not sure if it is relevant or not but I do have a slight coolant weep from the radiator.

Any advice on what is causing it?

[andrewrob]

schmooveboy said:

Going to bump this as I was having some problems this morning.

Any acceleration in my E38 728 harsh enough for a gear change caused the LPG system to switch off and switch back to petrol. I am thinking this would be a low pressure issue (tank is full) or perhaps a blocked filter but I am not sure.

It makes a beep when each injector is running on start up and there is always a longer pause between 1 and 2 so maybe number 2 has a tough start up for some reason. I thought it was just fuel surging around the tank but with a full tank as it is now that isn't really relevant.

It has done this sporadically since I bought it a couple of months ago. The LPG system was installed in Poland by the previous owner so I have no idea what system it is sadly. Last night it took 20 miles for the system to kick in. Not sure if it is relevant or not but I do have a slight coolant weep from the radiator.

Any advice on what is causing it?

It would be worth taking it into an LPG place to have the pump pressure looked at.
They can need adjusting from time to time, if its not pumping enough, that would cause it to fall back to petrol.
That's a long time for switching over. The switchover temp is adjustable when plugged into the gas ECU so probably worth getting them to check that too.
My E39 540 switches over within a mile even on a cold day, but the cooling systems on those are hotter than most so that probably helps with speed, but even so with yours 20 miles is way too long.
Where abouts in the country are you?

[schmooveboy]

andrewrob said:

It would be worth taking it into an LPG place to have the pump pressure looked at.
They can need adjusting from time to time, if its not pumping enough, that would cause it to fall back to petrol.
That's a long time for switching over. The switchover temp is adjustable when plugged into the gas ECU so probably worth getting them to check that too.
My E39 540 switches over within a mile even on a cold day, but the cooling systems on those are hotter than most so that probably helps with speed, but even so with yours 20 miles is way too long.
Where abouts in the country are you?

Winchester but I commute along the M3 to Surrey and spend a fair amount of time in Sussex. It wasn't as problematic this morning and the fact that the coolant leak bodge is holding makes me thing the evaporator wasn't coming up to temperature so maybe there is an air lock in that system. The LPG feed just seems very fragile and any big (ish) throttle inputs make it cut out so it has to be pressure related.

Can you recommend any LPG specialists to take a look at it in that area?

[andrewrob]

schmooveboy said:

andrewrob said:

It would be worth taking it into an LPG place to have the pump pressure looked at.
They can need adjusting from time to time, if its not pumping enough, that would cause it to fall back to petrol.
That's a long time for switching over. The switchover temp is adjustable when plugged into the gas ECU so probably worth getting them to check that too.
My E39 540 switches over within a mile even on a cold day, but the cooling systems on those are hotter than most so that probably helps with speed, but even so with yours 20 miles is way too long.
Where abouts in the country are you?

Winchester but I commute along the M3 to Surrey and spend a fair amount of time in Sussex. It wasn't as problematic this morning and the fact that the coolant leak bodge is holding makes me thing the evaporator wasn't coming up to temperature so maybe there is an air lock in that system. The LPG feed just seems very fragile and any big (ish) throttle inputs make it cut out so it has to be pressure related.

Can you recommend any LPG specialists to take a look at it in that area?

I'm afraid not, I'm up north so only know places around here.
Worth asking on here for a recommendation http://lpgforum.co.uk/

Have you got the high OBD on your E38 where its got the pixel screen under the gauges that comes up with messages like door open etc?

[schmooveboy]

Yes I do. It is currently telling me about a fog lamp being out but it has stopped telling me coolant is low (temporary fix is holding at the moment)

[andrewrob]

schmooveboy said:

Yes I do. It is currently telling me about a fog lamp being out but it has stopped telling me coolant is low (temporary fix is holding at the moment)

Do you know how to get into the hidden OBD? That will show you the exact coolant temp which could be useful for seeing at what temp the car is finally switching over to gas

[confused_buyer]

There is something wrong if it is taking 20 miles to switch. Most modern systems switch at 30 degrees coolant temperature which on a E38 petrol should be 1-2 miles even this time of year.