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Lpg keeps turning off
I was driving my p38 4.0 2001 hse and the system beeps at me the switches back to petrol it will switch back eventually but then 10 mins later converts back to petrol again BRC system I think
Can anyone help

Thanks

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Does it do it when you boot it or just when driving at constant speed? When it switches back to petrol, open the bonnet and check the reducer temperature, it should be bloody hot. That should narrow down whether it is a pressure problem or a temperature problem.

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Like I said in the other place, until you sort out your broken battery connector and have reliable electrics, there's no point in dealing with other issues that are most likely related to that anyway

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Especially if the main power feed to the LPG system is taken directly from the battery (as it should be if installed properly), an intermittent connection, even very momentary, will be enough for the solenoids to drop out.

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Cheers everyone it stops working when just after 10 mins. Just someone asked me to post on here as it might be something else the electric thing is in hand. I was told that it switches over on temperature

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That was me persuading another LPG powered P38 away from the dark side. It will changeover to gas when the reducer reaches a temperature that has been preset in the BRC software, it MAY switch back to petrol if the temperature drops below that preset level (some systems do, others don't). If you've got an airlock or poor coolant flow through the reducer, then it will heat up initially and switch to gas. As you drive the liquid Propane will cool things down as it vaporises but normally the coolant will provide enough latent heat that it doesn't matter. If the coolant flow is low due to a restriction or an air lock, then the vaporisation will cool the reducer down too much so it switches back to petrol. Run for another 10 minutes and the reducer heats up again so it goes back to LPG. If you've had an overheating problem so have lost coolant, particularly if the reducer is plumbed in parallel with the heater matrix and mounted fairly high in the engine bay, then it could be full of air.

The other possibility is that one of the solenoids drops out, gas pressure drops and the system switches back to petrol as it thinks you've run out of gas. It might be that you have a poor connection on the feed to a solenoid which heats up with current flow. As it heats up the resistance rises and the solenoid drops out, as the connection cools down, it will pull in again.

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Thanks. How do I find out if it's full.of air? And how do I get it out?
Sorry dumb on this subject how do.I find out if I have a bad connection on the feed to my solenoid
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Only you know how to get the air out as only you know how it is plumbed. Start the engine and let it run, feel the hose to the heater and also the hose to the reducer, they should be at the same temperature. Run the car on gas until it changes from gas to petrol, as soon as it does, open the bonnet and see what temperature the reducer is at then. If it's cold, then you've got air in it. You'll need to slacken the highest hose and bleed the air out.

Check the electrical connections to the solenoids, there will be one on the tank and another by the reducer. Make sure they are tight, not rusted and there aren't any cracks in the insulation. It's not uncommon for the insulation to crack and allow moisture in which will corrode the cable.

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Thanks for your help. I didn't have it fitted I bought it with it already done

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Even if you'd had it fitted, it's unlikely the installer would have told you how he'd done it. A photo of the heater hoses were they go to the reducer would help.

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I'm goin to get stuck in today I checked and the reducer was freezing cold and I'll get a few pics

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I've slackened the pipe I have liquid dropping out ov it but not switched to gasee yet

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Sorry can't up load pic keeps asking for link and I don't know how to upload load from my phone

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First you need to store the picture at a host like photobucket or similar. Then you copy the photoadress, write your post, click the 'image' button (5th from left in topbar) and paste the picture adress into the line.
That will show your picture here.

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If the reducer is freezing, that's your problem. Does the heater blow hot air?

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Yeah my heaters workin fine hot air cold air. The reducer is cold one pipe is warm the is hot running to the engine I'll try and upload now

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As richard says, it needs more bleeding, how high is your reducer in relation to your expansion tank ? If you need more height on the tank, give it a tug upwards, place something under while you bleed the pipework,,