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Rangie4fun



Member Since: 26 Mar 2014
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Austria 2013 Range Rover Autobiography TDV6 Barolo Black
cylinder fuel pressure; what is right or wrong??

Some time ago I ran trough all the functions of my IID tool on my Td6.
One of the functions I tested was the cylinder fuel pressure. Here are the numbers:
Cyl 1: -2
Cyl 2: 3
Cyl 3: -3
Cyl 4: 1
Cyl 5: -1
Cyl 6: 1

I don know what I'm looking at, but I should say they must be pretty same?

Car rans fine (cold and hot), starts immediately.

What does 'cylinder fuel pressure represent' ? Does it say something about injector health? fuel pump? or cylinder wear?
And what does the difference between these numbers indicate?

Thanks for your help! Bow down

Post #358104 22nd Nov 2015 5:02pm
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Mikey



Member Since: 10 Jan 2008
Location: Dundee
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More commonly referred to as "Injector Fuelling Compensation"

Measured in cubic mm's (mm³) it is measuring how much extra, or how much less fuel is being injected into each cylinder. Usually used to determine which cylinder is misfiring

Values of +1-2 are common, +3 should be monitored, and anything higher should be investigated, though you would likely feel a misfire at this point

99 times out of 100, it is a faulty injector. Less likely is a wiring loom issue, and even less likely is a mechanical fault with the engine, causing low compression

Thumbs Up

Post #358135 22nd Nov 2015 8:13pm
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Rangie4fun



Member Since: 26 Mar 2014
Location: Home sweet home
Posts: 146

Austria 2013 Range Rover Autobiography TDV6 Barolo Black

Hello Mikey,

Thanks for your explanation! Bow down Thumbs Up

Why is this compensation for injecting less or more fuel? Is it compensating a bad injector? and is a minus or a plus figure worse?
So i should keep an eye on it and see that cylinder 2 isn't going to get worse?

Post #358142 22nd Nov 2015 8:36pm
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Mikey



Member Since: 10 Jan 2008
Location: Dundee
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Positive figures are over fuelling, negative is under fuelling.

Generally speaking, negative figures can be ignored is most cases

The higher positive figures are from blocked/faulty injectors. The Engine ECU sees a "crank speed" on each cylinder. A lower tHan expected reading sees the ECU allowing in more fuel, hence the higher compensation figures

Post #358145 22nd Nov 2015 8:49pm
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Rangie4fun



Member Since: 26 Mar 2014
Location: Home sweet home
Posts: 146

Austria 2013 Range Rover Autobiography TDV6 Barolo Black

Monitored this morning. Cyl. 2 still has 3 and jumped incidentally to 4 and immediately returned to 3 again.

When revving up to 1500 or 2000 RPM all equalled at 0.
So is there a reason to worry? Since revving (and thus driving conditions) there is no difference at all between all cylinders.
Need to know if can go on holiday (2500 km) next week without making things worse or even get stranded? Question

Post #364100 27th Dec 2015 3:12pm
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Mikey



Member Since: 10 Jan 2008
Location: Dundee
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Scotland 

You may find you will have a slight misfire at idle at times

You can the some injector cleaner, that may help things Thumbs Up

Post #364119 27th Dec 2015 6:10pm
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Rangie4fun



Member Since: 26 Mar 2014
Location: Home sweet home
Posts: 146

Austria 2013 Range Rover Autobiography TDV6 Barolo Black

Hi Mikey,

Thanks again for your help! Bow down
So I understand that there is nothing to worry about when all are zero under load?
Going to use that injector cleaner anyway! Thumbs Up

Post #364128 27th Dec 2015 6:53pm
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Rangie4fun



Member Since: 26 Mar 2014
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Austria 2013 Range Rover Autobiography TDV6 Barolo Black

Update on this one. Finally got to replacing injector no. 2 Because injector cleaner wasn't doing anything. With only covering 3000km in the past half year the value of no. 2 increased to +4. So replacing seemed the best option. Fitted new (overhauled by Bosch) injector (came out really easily Very Happy ). Value on no. 2 is now +1 and all others are now on -1, 0 and +1. So everything seems back to normal Thumbs Up

Post #399264 5th Aug 2016 8:08am
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kingpleb



Member Since: 07 Jun 2011
Location: Maybe here. Maybe there, I get everywhere!
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United Kingdom 2005 Range Rover Vogue Td6 Bonatti Grey

This was from mine when it was faulty and had injector and HP issues
http://www.fullfatrr.com/gallery/albums/us...elling.pdf

I can try and get current readings but im sure an injector is leaking again from the small amount of smoke i get from where its parked up a few days Smile FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

Post #399614 8th Aug 2016 1:46pm
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Rangie4fun



Member Since: 26 Mar 2014
Location: Home sweet home
Posts: 146

Austria 2013 Range Rover Autobiography TDV6 Barolo Black

interesting table.
Is this doen with IDD tool? Can't recognise these figures.

Wondering what is wrong? engine speed 241 RPM and battery volts at 9.4 Question Question

Post #399637 8th Aug 2016 6:36pm
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kingpleb



Member Since: 07 Jun 2011
Location: Maybe here. Maybe there, I get everywhere!
Posts: 8455

United Kingdom 2005 Range Rover Vogue Td6 Bonatti Grey

Sorry thats cranking and with the bbs faultmate msv2 Smile FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

Post #399641 8th Aug 2016 7:35pm
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Rangie4fun



Member Since: 26 Mar 2014
Location: Home sweet home
Posts: 146

Austria 2013 Range Rover Autobiography TDV6 Barolo Black

that makes things clear Laughing so no very slow running car Razz

Post #399643 8th Aug 2016 7:43pm
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kingpleb



Member Since: 07 Jun 2011
Location: Maybe here. Maybe there, I get everywhere!
Posts: 8455

United Kingdom 2005 Range Rover Vogue Td6 Bonatti Grey

No 😂😂

I'll get a proper disc done at some point as it should be on here for reference for others really FFRR MY06 facelift With TDV8 Alloys Zeros/ATR's
Mantec Sump Guard, Rigid Load liner, MY10 BT upgrade.

Post #399646 8th Aug 2016 8:08pm
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