The engine management light came on om 2006 4.4 petrol engined Range Rover earlier this week. Diagnostics showed it was running lean and suggested changing the fuel pump. The pump is situated in the fuel tank and is lubricated by the petrol itself (so I am told). So far I have done 26,000 miles on my LPG conversion and it dawned on me that the pump may be getting a bit sticky through lack of use. I have decide to run on petrol only for a tankful and see if that works. So far the management light has stayed off. If it stays off my plan was to run on a tankful of petrol every three months or so to keep the pump lubricated.

What do you all think? I am certainly no mechanic and would appreciate feedback.

Cheers.

Pumps do wear out. Your car will run on petrol until the water is warm enough to vaporise the LPG. On mine it takes a couple of miles at this time of year. I can't see how running a tank of petrol through will make much difference, but I guess you can try it.

kirton

you're barking up the wrong tree

your fuel pump runs continuously , when you first start up you will run on petrol anyway until the threshold temp is reached then the system switches to lpg , but your petrol pump continues to run - it aint getting 'sticky' at all

BUT what could be getting sticky is your gas injectors (happens in cold weather more often), maybe change lpg filters if it hasn't been done for a while and run some injection cleaner through the lpg system.

don't take it back to whoever diagnosed a new fuel pump was needed - unless there's more your not telling us

It won't be the petrol fuel pump that's sticking. The LPG may need recalibrating and it will be the sensors that are throwing the management light and thus the code when the LPG is being used.

I hope this helps.

regards

John

PS what LPG system do you have, how much LPG can you get in the tank and what range do you get?

FWIW my fuel pump packed up at about 120k miles so they do fail. No warning, no EML, the car just wouldn't start one day. 03 4.4 V8 petrol / lpg. 1st of many hopefully. I love my Rangie

biggest culprit of fuel pump failure on LPG converted car's in general is lack of petrol in the tank, best thing to do is keep it over 1/4 at all times that way you should be safe

kirton wrote:

Diagnostics showed it was running lean and suggested changing the fuel pump.

Don't know what sort of suggestion that was but may I suggest you find a new mechanic...

If it's running lean on LPG then there is one thing it CAN'T be and that is the PETROL fuel pump...!!!!

And as Dingg1 said, the pump runs all the time to cool the injectors when running on LPG, the petrol side gets enough use for the few minutes each morning before the LPG cuts in..

Lots of reasons why it will run lean on LPG and put the MIL light on, from holed diaphragm in the vaporiser to a blocked filter etc

Time to get the LPG system serviced and checked....  Pete
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Turned out to be a failing oxygen sensor.

Replaced with a new Bosch sensor. Failed within 24 hours.
Fitted another Bosch sensor. Failed whilst still on the ramp!
Fitted Landrover Sensor. Seems Ok at present!!

@kirton, how did you find out it was an oxygen sensor? What was the fault code? Cost to replace?

Also, @daz, what did you replace the pump with? BMW or OEM or LR? Do you have a part number? Where did you buy a replacement?

Was driving back from London yesterday and as the lpg ran out and switched to petrol, it was a little bit jerky on the uphill bits. Got home fine but now starts and runs for 5 seconds before stalling. Thinking probably pump failure but interested in any other suggestions such as oxygen sensor etc.

Dolphinboy,

I cannot recall the code diagnosing the failing sensor but one of the symptoms was when starting from cold, the engine would fire then stop. if I then restarted with a tiny amount of throttle it would settle down. After having the sensor replaced, a small airleak was also discovered which complicated things. Since then I have bought a Prodiag OBD2 diagnostic interface and OBD Car Doctor Pro and have set it recording the sensors and MAP and have found no problems. I can see it would be easy to replace an oxygen sensor which is OK when the real problem is a small air leak.

Dolphinboy wrote:

@kirton, how did you find out it was an oxygen sensor? What was the fault code? Cost to replace?

Also, @daz, what did you replace the pump with? BMW or OEM or LR? Do you have a part number? Where did you buy a replacement?

Was driving back from London yesterday and as the lpg ran out and switched to petrol, it was a little bit jerky on the uphill bits. Got home fine but now starts and runs for 5 seconds before stalling. Thinking probably pump failure but interested in any other suggestions such as oxygen sensor etc.

My fuel pump just packed in last month and changed it with helpful a similar video as above. I have been told to keep it over 1/4 tank.

I was quite bad for leaving very little petrol in it.

Very good info did mine a couple of months ago and all was well pump nice and quiet . However after a week or two pump has became noisey . Pretty irritating hum all the time . Pump was x5 one £39 no issues with fuel pressure starting etc .Bought from eBay so contacted seller who has very kindly sent a replacement .not had time to change yet but am carrying spare pump just in case .
don't like the sound of pump humming all the time .I can confirm pump runs all the time even when on gas .If anyone knows how to shut this noisey pump up I would be most grateful.before I go to the bother of fitting a replacement just to find its the same