What about a 12v bulb on each injector???

It uses Piezo injectors, which need about 100 Volts at several Amps, so a low voltage bulb will fail.
I could use a suitably resisted LED, which might work, as it's a high impedance load.
 
Today I put the Delphi WOW on the FL2, to poke around the injector diagnostic stuff. I was surprised to see that it displays the injector codes, which is really useful.
I couldn't find this information on SDD, so I couldn't check the numbers with the injectors fitted to the engine.

I've found that the injector numbers in the ECU don't match the injectors in my engine.

I'm not sure if the coding makes much difference, and can't imagine it's the cause of the misfire.

However it might be worth coding the ECU to the injectors that are actually fitted, so that's tomorrow's job.

Unfortunately the working injector I ordered hasn't arrived yet, so I can't test the injector's by substation in turn yet.
 
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Try recoding them all 1st....Having just read up on piezo injectors they do sound like precision components. This could be your problem nodge....good luck dude.
 
Try recoding them all 1st....Having just read up on piezo injectors they do sound like precision components. This could be your problem nodge....good luck dude.

They are seriously precision items, I've read that just removing them can damage them. :(

I've also read that they can't be reconditioned too.

All the injectors in my FL2 are clean and rust free, so presumably they've been reconditioned to some degree or another. However I've no history on them, or how they've been treated. Going by the general quality of workmanship on this engine, it wouldn't surprise me if they'd been kicked into a muddy puddle before being fitted. :eek::oops:

One thing I'm not sure about. Would the codes new now be irrelevant, if the injectors had been pulled apart. :confused:
 
They are seriously precision items, I've read that just removing them can damage them. :(

I've also read that they can't be reconditioned too.

All the injectors in my FL2 are clean and rust free, so presumably they've been reconditioned to some degree or another. However I've no history on them, or how they've been treated. Going by the general quality of workmanship on this engine, it wouldn't surprise me if they'd been kicked into a muddy puddle before being fitted. :eek::oops:

One thing I'm not sure about. Would the codes new now be irrelevant, if the injectors had been pulled apart. :confused:


I can remember when the larger Daf trucks first went common rail (2006) and the tutor telling us the tolerances were so fine and the pressures so high there are actually no seals, the parts are such a good fit they dont leak! how true that is I have no idea?
He also told us the injectors could actually do 5 injections per stroke, but at the minute only two per (one pre main injection to keep engine nosie down) stroke were used, that will have changed with Euro6 I am sure.
 
He also told us the injectors could actually do 5

The LR manual says the same thing. ;)
Screenshot_20201121-184245_Adobe Acrobat.jpg
 
Interesting to read abuot the 10 bar leak off non return valve, I have heard of other common rail cars running same pressures on leak off lines, I started to suspect it was cause of inj prob on wifes old 54 plate 3.0 tdi, but got rid of before I could look inti it more, since learnt any audi pre 08 has potential for inj probs.
 
Interesting to read abuot the 10 bar leak off non return valve, I have heard of other common rail cars running same pressures on leak off lines, I started to suspect it was cause of inj prob on wifes old 54 plate 3.0 tdi, but got rid of before I could look inti it more, since learnt any audi pre 08 has potential for inj probs.

The 10 bar leak off pressure makes a leak off test irrelevant, and probably dangerous too.:eek:
I think it's pretty unique to this type of injector.
 
Actually thinking about it. I wonder if having a faulty leak off valve (lower than 10 bar) could stop a slightly fussy injector from working properly?


I carried out a leak off check on the audi and they were all pretty much the same flow wise (not used the kit since!) but the thing was puffing white smoke on hot idle, and was also a toss to start so at least one inj was defo on its way out.
The smaller 2.0tdi engine had gotten a real bad rep for inj issues, so bad audi were fixing loads foc even if out of warranty.
 
The LR manual says the same thing. ;)View attachment 223716
Hi Nodge, just reading through the w/s manual blurb you posted about the care needed when handling the injectors whos to say that coco the clown who worked on it before hadn't dropped one of the injectors? It does also say that replacement injectors must be coded to the ECM, did you say that none of the injector no,s match what's stored in the ECM currently ? If so, it's got to be worth a punt putting the correct no's in me thinks. You still may have a dodgy injector but putting the correct no's in will eliminate one potential problem. As ever best of luck.
 
Hi Nodge, just reading through the w/s manual blurb you posted about the care needed when handling the injectors whos to say that coco the clown who worked on it before hadn't dropped one of the injectors? It does also say that replacement injectors must be coded to the ECM, did you say that none of the injector no,s match what's stored in the ECM currently ? If so, it's got to be worth a punt putting the correct no's in me thinks. You still may have a dodgy injector but putting the correct no's in will eliminate one potential problem. As ever best of luck.

Coco the clown, I like that! Absolutely one of the injectors could have been dropped, I myself also allowed them to potentially drain of fuel, in the time it too me took me to rebuild the engine. Apparently they shouldn't be drained either, but it's too late to worry about that now. I'm wondering if one has got some grit in it, is faulty or been dropped, before I even bought the car. When I picked it up, it was definitely idling on 3 cylinders, but it was already hot when I got there. It actually idled pretty smooth, as although it was only firing on 3, the dead cylinder had no compression, so the engine wasn't slowing much on the dead stroke.
I also noticed that when I put my foot down, it dropped another cylinder, which it's still doing, so this issue isn't something new. Unfortunately it's now more obvious, as it's got compression in all cylinders, so when one drops when cold or under load, it's very noticeable.

Second point about coding.
Yes the injectors codes need to be stored in the ECM/ECU/PTM, so accurate fueling calculations can be done.
None of the injector codes in my ECU match the injectors in the vehicle. However I don't know if this was the case with the old ECU. I don't know if SDD copied the codes from the old ECU to the new ECU, or simply left the old injector codes in the old ECU, only overwriting the immobiliser/VIN no.

However after running various calibrations on the new ECU, the engine definitely runs better now off load when hot than it did. In fact it shows no real running faults at all off load when hot, which is why I believe it's an injector that's causing this issue, I just don't know which one.
I will however run the coding routine, so I can get the injectors working the way they should.
 
Coco the clown, I like that! Absolutely one of the injectors could have been dropped, I myself also allowed them to potentially drain of fuel, in the time it too me took me to rebuild the engine. Apparently they shouldn't be drained either, but it's too late to worry about that now. I'm wondering if one has got some grit in it, is faulty or been dropped, before I even bought the car. When I picked it up, it was definitely idling on 3 cylinders, but it was already hot when I got there. It actually idled pretty smooth, as although it was only firing on 3, the dead cylinder had no compression, so the engine wasn't slowing much on the dead stroke.
I also noticed that when I put my foot down, it dropped another cylinder, which it's still doing, so this issue isn't something new. Unfortunately it's now more obvious, as it's got compression in all cylinders, so when one drops when cold or under load, it's very noticeable.

Second point about coding.
Yes the injectors codes need to be stored in the ECM/ECU/PTM, so accurate fueling calculations can be done.
None of the injector codes in my ECU match the injectors in the vehicle. However I don't know if this was the case with the old ECU. I don't know if SDD copied the codes from the old ECU to the new ECU, or simply left the old injector codes in the old ECU, only overwriting the immobiliser/VIN no.

However after running various calibrations on the new ECU, the engine definitely runs better now off load when hot than it did. In fact it shows no real running faults at all off load when hot, which is why I believe it's an injector that's causing this issue, I just don't know which one.
I will however run the coding routine, so I can get the injectors working the way they should.
If the replacement ECU kept the codes it came with perhaps the fueling calculations are nearer for the injectors that are fitted & along with your 'various calibrations' has it running better or if the 'old' codes were transferred to the new ECU perhaps it was just your 'various calibrations' that has it running better. However I'm with you it's got to be an injector problem.
Once you get the current injector codes stored in the ECU it might, & I'm sure we'll all have fingers crossed for you, cure all the running problems, otherwise it will be a case of somehow tracking down the faulty injector.:(
 
So why did you have to rebuild the engine/head nodge? I must have missed that part..
 
I think I read he found a nut in one of the cylinders?

I think all the previous work was carried out to try to eliminate this misfire.

Unfortunately the person doing the work wasn't very competent, allowing a nut to enter the intake.

Things I know to date are.

The inlet manifold is dated 2010, so is definitely not original.
The cylinder head has been reconditioned to some degree, and it definitely had a new inlet valve on No1 cylinder. I assume this was due to a dropped swirl flap.
It's had 1 new injector (it's in No1), and what appears to be reconditioned injectors in the order 3 cylinders.
The timing belt, water pump, tensioner, idler and crank pulley were all new.
The coolant was clean as a whistle.
The head gasket was new, as would be expected with a recent head rebuild.
There were various incorrectly located nuts and bolts around the engine.
There is evidence of probing on the injector harness, particularly for No3 injector (potentially the one with the issue).
The ECU had been in-expertly pulled apart, which is why I wanted to change it.
The injector codes don't match between the codes stored in ECU, and the numbers on the injectors. However I don't know if these were copied over from the removed ECU, or from the current ECU former injectors.

The apparently tested and working injector has arrived, so I'll fit that at the weekend, as well as disconnecting each injector in turn, to find the one that's not working.
My money is on No3.
 
Here's some pictures of the issue I found, when I stripped the engine down.
No 2 piston was in a bad way.
20200802_144506.jpg

The head was in a mess, but I believed it salvageable, as the valves had protected the seats from damage, or so I thought. I'll come back to this later.
20200802_144443.jpg

This is what remains of the nut, which I believe to be the missing EGR to manifold flange nut.
20200802_144532.jpg

These are the valves I pulled out of No2.
20200802_152522.jpg

This is the replacement piston, I got to replace the damaged one.
20200806_185802.jpg
 

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