rangerovers.pub
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Hi @LPGC, you seem to be the god with LPG conversions (although same question is for anyone who knows LPG well). Mines started to switch over after a longer time than normal. It used to switch within about 2-3 minutes, temp needle just off the cold pin, however it's now at least 8 mins and engine temp needle is just under half way.

It's PRINS if that makes any difference!!

I've had a search for the diagnostic software but drawn a blank.

Thank-you in advance

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What's the coolant level like? If it's low then you may have less flow so taking longer for the reducer to get up to temperature.

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Coolant level is correct. Check it weekly!

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When you think it's warm enough to change over have a feel of the reducer to see if it feels warm, if it's mounted high up there could be an airlock in it.

Could be a problem with the reducer temp sensor or it's wiring.

Prins ignition (RPM sensing) modules often fail, the Prins VSI ECU's could be damaged by voltage spikes on the rpm wire, so if the system gets it's RPM feed from an ignition coil or from a cam sensor an RPM module is probably fitted. If the ECU doesn't see an RPM signal it will never change-over to LPG, and if it loses the RPM signal while running on LPG it may switch back to petrol without the driver knowing (no beeps from the switch etc). There are various types of Prins RPM module, something around matchbox size with a few wires coming out of it or something that looks very much like a relay.

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Thanks, I’ll have a poke around and see what lurks beneath all the cable ties and insulation tape!

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Gilbert or others on LPG, please remind me what plugs you find are best in P38's? I've just been asked the same question in an email, he has Champion plugs in at the moment.

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Ugh, Champions, how to make an engine misfire when there's nothing at all wrong with it..... if GEMS, NGK BPR6ES, if Thor NGK PFR6N-11.

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Thanks Gilbert, I passed that info on to the owner. I recently advised this owner to join the pub forum.

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I’m using ngk’s

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Still the same problems j-rov ?

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So, noticed a cold cabin (HVAC) so put 2 and 2 together and thought the heater matrix might be blocked. Tried flushing and water flowed freely. So since my reducer is plumbed in series, put the host on that too and it barely let any water through. Tried on the other port and same, so must have an internal blockage. That'll explain why the LPG isnt working properly.....

Guessing the coolant should flow unrestricted...

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Yes it should be. I've had an OMVL R90E, BRC AT90 and eGas reducers all plumbed in series and no restriction to the flow on any. Maybe something is stuck inside it?

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Pulled it apart. Rubber membrane has a tear and lots of crystallised coolant stuck the wrong side of it, restricting the flow.

Service kit ordered. Hope that will be the end of it. Although, I might replumb to be in parallel one day.

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All that will do is increase the length of time it takes to change over. Parallel is only really needed if the heater system closes off the flow when you don't want heat. I was checking something else on mine with the Nanocom earlier today and for a coolant temperature of 83 C the heater matrix temperature was at 76 C, so that's 7 degrees being lost through the vaporiser.

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OK, will leave it series then and renew the pipes as they look a bit crazed now. Hope the service kit comes soon as this petrol stuff is well expensive!!!

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Is the reducer mounted high in the engine bay? More chance of it drying out when the engine is off if it is and that can lead to crystallisation and other problems. To keep it full of water when the engine is off it shouldn't be higher than water in the expansion tank.

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it is a bit high to be fair but the outlets are way lower than the expansion tank.

All working again now fortunately...