P38 4.6 hse

hey folks. got my self a p38 4.6 4 months ago and hate it. had a 3.5 manual discovery before the p38 and it was a pulling machine. never died on hills and was good on fuel. the p38 is on gas aswell as the old disco.
The p38 just has no pulling power at all and does 75 miles to 50 litres of gas. even running on petrol it gets roughly the same so costs a fortune to run.
the old disco would do 160 odd miles to 60 litres which i thought was good for what miles i do.
Basically i'm just asking for advise on it to see if anyone thinks it has a big problem or if its just a simple job to make it pull better. if it sees a hill it dies down and no matter how far you push the throttle it goes no better untill you kick the pedal down and let it rev like f**k
I'm also new to the forum so hello.

Sounds ****ed to me

When was it last seviced?

serviced it myself when i got it
new plugs
oil and filter
new leads
new gearbox oil and filter
think that was it

Only time ive experience low mpg and no pull was with a burnt out coil pack and not firing on all pots, watch this space there'll be plenty ideas off some of the guys

it all seems well at the sound of the engine. it ticks over nice and sounds well when revving away but just no guts at all. it sees hills and thinks........ NO. i dread to think what it would be like with a heavy load on. it pulls the same on gas or petrol so not sure what the fault could be

get your lpg looked at it should be doing better than that, and no way should a 4.6 be sluggish up hills..

j the range said:

get your lpg looked at it should be doing better than that, and no way should a 4.6 be sluggish up hills..

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I thought the same or i wouldnt have bought one. on level roads it got plenty of power it sings on but soon as a hill comes up thats it. If you stop on a hill and set off with foot down it goes well enough but foot as to be down. old 3.5 LPG discovery would pull anywhere. wish i never sold her

i would take it to somebody and have the fuel trims looked at, it sounds like it is not getting what it needs. dont take it to a cowboy take it to somebody that undrstands rover v8s..

j the range said:

i would take it to somebody and have the fuel trims looked at, it sounds like it is not getting what it needs. dont take it to a cowboy take it to somebody that undrstands rover v8s..

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I just sent my BECM away today because it came up with KEY CODE LOCKOUT and tried everything to get it sorted. I'll take it to cumbrian landrovers and see what they can do. they are usually good at coming up with a fix.

Gary8150 said:

I just sent my BECM away today because it came up with KEY CODE LOCKOUT and tried everything to get it sorted. I'll take it to cumbrian landrovers and see what they can do. they are usually good at coming up with a fix.

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Sending your BECM away for a keycode lock out was a bit premature, should have tried the EKA code.

Datatek said:

Sending your BECM away for a keycode lock out was a bit premature, should have tried the EKA code.

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Tried code over 50 times. Rang Lloyd landrover twice to make sure I had right number on my card but nothing. Tried the second position key idea and that didn't work so getting it decoded and just use the key in the door. Simple

I've never driven a Discovery V8 but I know the 4.6 requires a lot of pedal travel before it'll really start to move. If you're not used to it, it gives the impression of not having a lot of go unless you really floor it. It's just the way the throttle pedal is set up. Is this part of the problem?

Derek Ward said:

I've never driven a Discovery V8 but I know the 4.6 requires a lot of pedal travel before it'll really start to move. If you're not used to it, it gives the impression of not having a lot of go unless you really floor it. It's just the way the throttle pedal is set up. Is this part of the problem?

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Yep i aggree, mine is crap untill you floor it, goes along way down!! As for mpg my single point lpg system gets me 135 miles to 44lt of gas on a run, about 120 round town.

right i see. it might just be normal then. i just expected it to pull well up a hill with out flooring it. i live out in the sticks so alot of up and down hills which will make it work hard. just after getting out the 3.5 discovery into a 4.6 range rover you expect it to pull as well if not better let alone pull worse

I think you've a problem. A 4.6 pulls harder than any 3.9 or 3.5 even in a rangie p38 that weights more than a disco or a rang rover classic.

any sugestions? getting to the stage now where as i feel like setting fire to it or ringing up our local scrap man and say come and collect this piece of ****. it has a big hesitation when i give it some throttle. sort of splutters. but doesn't do it on LPG. it will go like f**k if i keep my foot to the floor but then i get 50 miles to 50 litres of LPG

Setup to run on LPG only??

Mine pulls fine on hills, even fully laden, but to get the best out of her I switch into sport mode and drop her into third, or even second if it is steep. If I don't do this, she's always trying to change up and the power fades away until she realises what's happening and drops down a gear herself giving the impression of very sluggish performance. Perhaps this is what you are experiencing? Try experimenting with sport and gears and it should also reduce the over-revving. I don't find it has a noticeable effect on mpg as it tends to smooth everything out.

Gary8150 said:

any sugestions? getting to the stage now where as i feel like setting fire to it or ringing up our local scrap man and say come and collect this piece of ****. it has a big hesitation when i give it some throttle. sort of splutters. but doesn't do it on LPG. it will go like f**k if i keep my foot to the floor but then i get 50 miles to 50 litres of LPG

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I'd bring it to a Testbook. I'm 100% sure that you have a problem like a oxygen sensor or a dirty MAF. That horrible fuel economy tell you everything.

Testbook will tell you what it is exactly. Replace oxygen sensors or clean the MAF and you'll be fine.

Power and fuel/gas economy