04 Td4 lumpy idle

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guineafowl21

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Inverness
....and occasional hard starting. 156k miles.

I did a simple unplug test, which wasn’t conclusive but seemed to indicate injector 3. I swapped that for a scrap injector (I know...) but no real improvement.

Plugged in the iCarsoft i930 and looked into the cylinder roughness data. Various readings of 744-800 (is this rpm per cylinder?). LP 340 and HP 30,000.

Fuel compensation data showed some on -1.77 and some on 20 (mm3? iCarsoft are bad at including units). Injector 1 was showing the highest values so I put the original inj 3 in there, and got an improvement. So it looks like inj 1 was the culprit after all.

Interestingly, selecting the cylinder roughness display now causes roughness at idle. I guess the question is, does anyone here have an iCarsoft, and how do they use it to diagnose injector issues? Is there a guide online?
 
I have an i930 and a Td4 with an injector fault! Never tried the fuel compensation and cylinder roughness functions. Will try to find them and have a play then report back. Can't find a guide anywhere. I have emailed their tech support before and it was useful.
 
I have an i930 and a Td4 with an injector fault! Never tried the fuel compensation and cylinder roughness functions. Will try to find them and have a play then report back. Can't find a guide anywhere. I have emailed their tech support before and it was useful.
It’s in diagnostics, smart scan. Now it’s running OK the compensation readings are still away from 0, but they stay reasonably constant. There must be a general guide to scantool common rail diagnostics somewhere, but I can’t find a decent one.

The car was filled with petrol and run till it stopped (not by me!) about a year ago.

Let me know how you get on.
 
Mine doesn't give any compensation readings on roughness, but mine isn't running rough.
All zero on compensation or roughness? My scanner gives roughness readings around 750-800 which I assume is rpm per stroke. It would be nice to have reference ranges for what’s acceptable.
 
Roughness up to 1-1.2 % is acceptable. In doubt.. does it still have the egr? That can become very ugly on Freelander injectors
 
OK, found fuel comp and roughness. On mine they are under live data. All show a reading of 0 all the time! When did you buy your i930? Maybe mine needs an update as I have had mine for 3 or 4 years. But the smoke at start up is now smoke all the time! Rough idle is smoothed by disconnecting injector 3 so I will start by substituting that one. Shame the readings don't work but I don't understand where the ecu would get that injector specific data from on a common rail system??
 
. On mine they are under live data. All show a reading of 0 all the time!
Mine it the same. But it runs smoothly, so I put it down to there being nothing to compensate. Or the I930 is very hit n miss. Mine doesn't read codes from the TCM, but strangely it reads the module information file. :oops:
 
OK, found fuel comp and roughness. On mine they are under live data. All show a reading of 0 all the time! When did you buy your i930? Maybe mine needs an update as I have had mine for 3 or 4 years. But the smoke at start up is now smoke all the time! Rough idle is smoothed by disconnecting injector 3 so I will start by substituting that one. Shame the readings don't work but I don't understand where the ecu would get that injector specific data from on a common rail system??
Bought mine a few months ago. Readings of zero either mean your engine is running perfectly (yay!) or that the scanner isn’t communicating, I would suggest. As I say, my version gives roughness readings from 750-800 ish, so I guess this is rpm, so shouldn’t be zero anyway.

Roughness (rpm per cyl) could be measured by the momentary change in engine speed (from crank sensor) after each cyl fires.

Fuel compensation probably a direct reading of the injector pulse pattern plus HP rail readings.
 
Roughness up to 1-1.2 % is acceptable. In doubt.. does it still have the egr? That can become very ugly on Freelander injectors
Wow, then mine really is rough - say one cyl was 744, then I have a range of about 735-751. Mine was nowhere near that. It does have the EGR, but the injectors I took out looked reasonably clean.
 
Just done update on my i930 and same version software loaded. Have emailed icarsoft tech support to ask why these 2 things don't work. I also found an email asking why it didn't connect to auto box, sent by me in 2014 and the response was 'will be covered in later release'!
 
Just done update on my i930 and same version software loaded. Have emailed icarsoft tech support to ask why these 2 things don't work. I also found an email asking why it didn't connect to auto box, sent by me in 2014 and the response was 'will be covered in later release'!
How did you do the update? I can’t seem to find the manual.
 
I also found an email asking why it didn't connect to auto box, sent by me in 2014 and the response was 'will be covered in later release'!

My I930 is on the latest SW version, and still doesn't read gearbox codes. However it does read the TCM information file and some live data. The I930 is a cheap unit, but if Icarsoft say it will connect to the various modules, then it should.
 
Icarsoft replied, far too quickly to understand the issue, and advised using OBD option. I advised it was a pre 2004 diesel!! Gone back to them again. If gf21's works then I want mine to work! Please can gf21 advise his software version? It is on the Help menu. Thanks. Also, I don't have Smart Scan options, my data is in the live data menu.
 
Thanks, that'll be it then. The V2 seems to work better! Am in dialogue with icarsoft tech support. Might be able to swing an upgrade. In the meantime I took all injectors out, 2 were black and gooey. Substituted 2 spare ones. Will see how it is now when cold.
 
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