Anyone able to put my mind at ease or tell me this isn’t normal and pint me the right way:


Long story short had her a couple of years now and had variiis faults causing engine to run lean - ultimately was bad o2 x4 and the maf, and a couple of vac leaks....

This was fixed then no faults appeared.

I then recently had a rich fault both banks and smoke tested and the only leak was from the oil neck seal so it was losing pressurised air there.

Fixed this no lights but this time for one reason or another I hooked up my scanner and it’s odd,

At idle both long term trims are 0- 2ish which is ok I think but the short term on both banks dances around from +8 to -8 and is all over the place - I guess it averages a 0 as it swings to sides but is this normal if not any ideas?

When driving it’s pretty similar and no issues driving it, except when I plant it at 5500rpm it goes about +18 both banks each and every time? Again normal or not?

May or may not be related but car seemed to run out of fuel even though the range said 30miles the other day - by some miracle it was as I was coming into my village as I lost all power i out it into neutral and coasted outside my house where I had a Jerry can luckily...

Anyway any ideas I’m praying someone say oh yes I had these exact symptoms  Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

You have no symptoms, it's all good, stop about and drive it 🙄

Oh and put some fuel in it 😂😂

I just wondered if it was early onset dying fuel pump as it shouldn’t die with miles left on range and it could tie a lot of it together - don’t suppose you have a scanner so you could see if yours is the same at idle? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

It will die if its got sweet fa to pump at 30 miles range on a dodgy transmitter it's empty as you've proven.

so you reckon its a dodgy transmitter? looking at previous posts there is a jet pump between the two halves of the tank which fails so it says there is decent range left as it is only measuring from one side but the other side is in fact empty - could it not be this? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

Fill the up, if it's showing 30 miles range it's almost empty.

There's nowt wrong with the fuel trims either

Ok, I get the idle fuel trims are fine cheers but should it go lean at WOT though?

Also I think you are wrong with regard to range - my 4.4 l322 would go down to 1 then --- when it was empty, this thing the orange light comes on and five miles later its empty that definitely is a problem I'm sure of it otherwise it would count down to zero surely? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

I despair

right - so lets just picture this - you bought a brand new Range Rover and it said you had 30 miles in the tank.. .then it ran out of fuel you'd be happy with that? if that's the case more fool you. Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

I'm a bit confused - what exactly is the problem that you are trying to cure? what are the fault codes?
If the only issue is that you ran out of petrol when the computer told you there were 30 miles left then there is a very easy fix for this that will also increase the life of the fuel pump.
Your car, like all of mine, is an obsolete model that is a lot closer to the end of it's life than the start. This is why we can buy them for a tiny fraction of the new car price, I can easily accept that it won't be perfect in return for a saving of tens of thousands of pounds.
If it were mine I would just enjoy it, keep changing the oils and fix things if they break, modern cars are very clever with lots of systems to warn us of problems, they really don't need us to go looking for problems.

Forgive my two ha'pence worth but why are you relying on the trip computer range rather than the actual fuel gauge?
The range remaining is only an approximation and accuracy will vary considerably depending on driving style, gears being used etc, etc. The internal fuel range consumption value displayed in the on-board computer is calculated using the figures for average tank contents and the distance travelled since the last reset.
The fuel range value displayed is calculated using the same figures to show the available range with the remaining fuel in the tank. As with mpg display accuracy is dependant on the system being set up correctly or even calibrated but there are many other variables affecting consumption that can't be accounted for including ambient temperature variation, air density etc. In short "Range" is a rough guide only not a factual limit. In any case running the tank below 1/8th remaining fuel is only asking for trouble with any car not just fattys.

Hi Nobby - using both the orange light comes on it say 30miles ish and does not long after - surely both shouldnt have failed like that.

I get what people are saying it’s an old car etc but my 2002 with 200000 miles was accurate I had as low as 10 miles in it and the reserve light worked as it should have so I don’t get that? Current stable:
2006 BMW M6
2007 4.2 V8 S/C FF
Gone:
2002 4.4 V8 FF

I don't think anything has failed.
The orange low fuel light starts to glow when you have roughly just about 2 gallons and fully illuminates when you are getting close to fumes. 2 gallons left rattling around the tank doesn't give you much range unless your coasting in top gear on a motorway. You don't say what sort of journey you were on - if short and local what sort of mpg do you expect - low teens maybe? As I said your "range" display is based on average readings since the last reset. Yes it should count down to empty i.e. --- but like any simple computer if it doesn't have the right info in the first place the result will not be 100%. For example if you've changed tyre or wheel sizes from factory standard but not put in the changes in the config file then that also alters the way its trying to calculate the variables. I would always consider that the info on MPG etc is about 4% higher than true.
I may be wrong but with so little fuel sloshing about in the tank you could also be at risk of sucking any sediment or even air/vapour into the fuel lines and filter. Honestly, never run it that low cos your tempting fate

Common sense has arrived
Hallelujah