1.9jtdm injector leak check.

[Davey_saxo]

Hi all,
Has anyone carried out an injector leak back check on a 1.9JTDm and if so what results did you get. I have read that it is quick and easy way of showing blocked or partially blocked injector. My 1.9 is idling a little rough and would like to try the check, but wanted some advice first.

Cheers
Dave C

[Davey_saxo]

I assuming that's a big NO then....oh well.

[sussexa]

think it may possibly show a potentially worn injector also, really all it can do is show the balance of leak by between the injectors.found a few good videos on you tube on common rail injector testing and servicing.
have you tried a strong injector cleaner, i have used forte and bg244(i think it was).
out of the you tube vids this guy seemed most usefull, he has a few on there.
http://www.youtube.com/watch?v=LFCGNHQ5138

[sussexa]

did you ever get them tested?
i bit the bullet and bought a test kit off fleabay, but warning check the any kit closely before using, i bought a neilsen kit and found 4 of the 6 connectors not properly drilled out and therefore dead ended.
anyway drilled out and cleaned and here are test results
idle test 5 mins
http://img243.imageshack.us/img243/9...dle5minswi.jpg Uploaded with ImageShack.us

2000rpm approx 2 mins
http://img15.imageshack.us/img15/989...000rpmwith.jpg Uploaded with ImageShack.us

these are injector values off fes
inj correction cyl1 = 0.15mm3/i injector code 8SAPHOCAA
inj correction cyl2 = 0.35mm3/i injector code 8HISE6AAA
inj correction cyl3 = -0.52mm3/i injector code AHSLC2AAA
inj correction cyl4 = 0.02mm3/i injector code AHZIDTAAA

taken as % from an average of total flow
------------------ at idle ----------------- 2000rpm
cylinder 1 = ------- 91.5% ------------------ 91.5%
cylinder 2 = ------- 108% ------------------ 103%
cylinder 3 = ------- 91.5% ------------------ 91.5%
cylinder 4 = ------- 108% ------------------ 114.5%

at idle max variation = 16.5%
at 2000rpm max variation = 23%

no idea if these are too far out of balance?
but 1 and 3 are lower at idle and 2000rpm
are 1 and 3 injecting too much or are 2 and 4 leaking back too much?

heres a vid on idle to give idea of flow rates
http://www.youtube.com/watch?v=AvsGKk-Yh1c

[Davey_saxo]

Na, in the middle of trying to find a new job. But I did remove the injectors to take a look and found 2 injectors had deposits on the tips. I cleaned the deposits off (very carefully) and refitted the injectors. The car MPG has risen from 35MPG to 39.2MPG.

I'm trying to find out some more about the injectors and cleaning them, I came across and American forum which had a link to a diesel injector company which was overhauling injectors and coating the needles to prevent wear and problems caused by the new wave of Ultra Low Sulphur diesels.

My Xmas list is getting longer....new wheels, paint thickness gauge, injector overhaul, remap, FIATECUSCAN
But on the bright side the carbon interior is still holding up alright.

Cheers for the reply, I'll keep you updated.

[TribesMan]

Well to me that doesen't look like "too much", but it is not the best.

AFAIK Bosch say that correction factors above 0.9mm^3/inj mean that there is a problem.

[sussexa]

the avg price for recon injectors seem to be around £105-130 plus your injector back but if you search for pf jones theyre listing £85 i think it was plus your injector back if theyre 0110445243.
edit £89
http://www.dieseljones.co.uk/common-...rail-injector/

no recommendations of them its just cheapest ive found so far.

[alid1]

Originally Posted by sussexa

did you ever get them tested?
i bit the bullet and bought a test kit off fleabay, but warning check the any kit closely before using, i bought a neilsen kit and found 4 of the 6 connectors not properly drilled out and therefore dead ended.
anyway drilled out and cleaned and here are test results
idle test 5 mins
http://img243.imageshack.us/img243/9...dle5minswi.jpg Uploaded with ImageShack.us

2000rpm approx 2 mins
http://img15.imageshack.us/img15/989...000rpmwith.jpg Uploaded with ImageShack.us

these are injector values off fes
inj correction cyl1 = 0.15mm3/i injector code 8SAPHOCAA
inj correction cyl2 = 0.35mm3/i injector code 8HISE6AAA
inj correction cyl3 = -0.52mm3/i injector code AHSLC2AAA
inj correction cyl4 = 0.02mm3/i injector code AHZIDTAAA

taken as % from an average of total flow
------------------ at idle ----------------- 2000rpm
cylinder 1 = ------- 91.5% ------------------ 91.5%
cylinder 2 = ------- 108% ------------------ 103%
cylinder 3 = ------- 91.5% ------------------ 91.5%
cylinder 4 = ------- 108% ------------------ 114.5%

at idle max variation = 16.5%
at 2000rpm max variation = 23%

no idea if these are too far out of balance?
but 1 and 3 are lower at idle and 2000rpm
are 1 and 3 injecting too much or are 2 and 4 leaking back too much?

heres a vid on idle to give idea of flow rates
YouTube - injector test idle video

These values are ok. I suggest you check your swirl valve operation on the intake manifold,chances are the rod may have come off the pivots.

[sussexa]

not driven car since testing above, car now smoking like a bugger on start up and knocking like an old cortina with nackerd cams,definately seems like running on 3 cyliners.as soon as driving down road smoke stops and running smooth, once warm blasted for a bit and not lost any power and very smooth on boost but pulling off say from a junction approx 1300-1500 revs knocking again? starting to think damaged injector when the test kit blocked the leak off pipe or ive got a sticky piston ring?
when parking up at trip end no smoke and running fairly smooth?
any recomendations to rule out piston ring other than compression/leak down test, will a few drops of oil down glow plug holes help(mobil1 0w40)

[alid1]

Originally Posted by sussexa

not driven car since testing above, car now smoking like a bugger on start up and knocking like an old cortina with nackerd cams,definately seems like running on 3 cyliners.as soon as driving down road smoke stops and running smooth, once warm blasted for a bit and not lost any power and very smooth on boost but pulling off say from a junction approx 1300-1500 revs knocking again? starting to think damaged injector when the test kit blocked the leak off pipe or ive got a sticky piston ring?
when parking up at trip end no smoke and running fairly smooth?
any recomendations to rule out piston ring other than compression/leak down test, will a few drops of oil down glow plug holes help(mobil1 0w40)

If you feel that a injector is faulty, i have a recon injector if your interested. I also have 4 working used injectors.

[losa]

Originally Posted by sussexa

did you ever get them tested?
i bit the bullet and bought a test kit off fleabay, but warning check the any kit closely before using, i bought a neilsen kit and found 4 of the 6 connectors not properly drilled out and therefore dead ended.
anyway drilled out and cleaned and here are test results
idle test 5 mins
http://img243.imageshack.us/img243/9...dle5minswi.jpg Uploaded with ImageShack.us

2000rpm approx 2 mins
http://img15.imageshack.us/img15/989...000rpmwith.jpg Uploaded with ImageShack.us

these are injector values off fes
inj correction cyl1 = 0.15mm3/i injector code 8SAPHOCAA
inj correction cyl2 = 0.35mm3/i injector code 8HISE6AAA
inj correction cyl3 = -0.52mm3/i injector code AHSLC2AAA
inj correction cyl4 = 0.02mm3/i injector code AHZIDTAAA

taken as % from an average of total flow
------------------ at idle ----------------- 2000rpm
cylinder 1 = ------- 91.5% ------------------ 91.5%
cylinder 2 = ------- 108% ------------------ 103%
cylinder 3 = ------- 91.5% ------------------ 91.5%
cylinder 4 = ------- 108% ------------------ 114.5%

at idle max variation = 16.5%
at 2000rpm max variation = 23%

no idea if these are too far out of balance?
but 1 and 3 are lower at idle and 2000rpm
are 1 and 3 injecting too much or are 2 and 4 leaking back too much?

heres a vid on idle to give idea of flow rates
YouTube - injector test idle video

Hm, these values looks just fine.
First M-JET engines had tolerance of +/- 0,9, and later had tolerance +/- 0,5.

But, I have seen M-JET engines with injection correction from -1,8 to +2,5 at idle (but very low at 2000rpm) and still running, so hard to tell...

Originally Posted by sussexa

not driven car since testing above, car now smoking like a bugger on start up and knocking like an old cortina with nackerd cams,definately seems like running on 3 cyliners.as soon as driving down road smoke stops and running smooth, once warm blasted for a bit and not lost any power and very smooth on boost but pulling off say from a junction approx 1300-1500 revs knocking again? starting to think damaged injector when the test kit blocked the leak off pipe or ive got a sticky piston ring?
when parking up at trip end no smoke and running fairly smooth?
any recomendations to rule out piston ring other than compression/leak down test, will a few drops of oil down glow plug holes help(mobil1 0w40)

If one injector is not working (as you suggest engine is running on 3 cyl) ECU would register that error.

Try a clasic test, when engine is idling, put a screwdriver on each injector and close to ear, so you will notice which one produces strange sound's.

Also disconnect connector's and spray them with some WD, and see if there is some diference.
Aparently there are some known issues with 3rd injector connector on those 1.9 16V JTDM/CDTI engines:
Vectra C / Signum Owners' Club Forums - View Single Post - Vectra 1.9 CDTI [150] performance issues

[TribesMan]

From my experience, if you get correction above 1.5mg/inj, engine starts to sound and run very rough, especially when idle.

A friend of mine had a problem with his 1.9 JTD 120HP and it got corrections around 2mg, whole car was shaking while engine was idling. But interestingly engine started to run smoother if you engaged the air conditioning.
But that was not the only problem, it was also smoking badly when accelerating hard.

[sussexa]

those correction values were taken off fes a while before(maybe months) i did those leak off tests(everything running nice),ill try to read them again now its running rough and see whats different tomorrow.

[sussexa]

clear as day now.
starting car from cold 0.5'c
at idle
inj correction cyl1 = -5.20mm3/i these look like a assisted start to add more fuel?
inj correction cyl2 = +5.01mm3/i
inj correction cyl3 = -5.08mm3/i
inj correction cyl4 = +5.18mm3/i

at 2000 rpm

inj correction cyl1 = -3.34mm3/i
inj correction cyl2 = -1.23mm3/i
inj correction cyl3 = -0.63mm3/i
inj correction cyl4 = +5.04mm3/i

after a few minutes running

inj correction cyl1 = -4.95mm3/i
inj correction cyl2 = +0.6mm3/i
inj correction cyl3 = -0.7mm3/i
inj correction cyl4 = +5.04mm3/i

cleaned plugs with contact cleaner

inj correction cyl1 = -2.1mm3/i
inj correction cyl2 = -1.5mm3/i
inj correction cyl3 = -0.7mm3/i
inj correction cyl4 = +4.04mm3/i

so definately looks like 4 is a gonna possibly 1 also

how does the ecu calculate the correction value?is it worked out from a calculation from rail pressure drop when it knows injector should be open?

definately looks like damage been done when leak back connectors blocked on 3 and 4 during 1st test.

[TribesMan]

Wow... those seem to be way off... :/

Get them reconditioned. Here in Slovenia you can get injectors reconditioned at the local Bosch service for about 80€ per piece. I think it would be the best idea to get all 4 done at the same time, because even 2 and 3 doesent seem to be in the best shape IMO...

how does the ecu calculate the correction value?is it worked out from a calculation from rail pressure drop when it knows injector should be open?

AFAIK ECU measures the differences in rotation speed of the crankshaft while engine is running. If one injector flows more fuel than the others or the nozzle on one of the injector is partly clogged that will represent in different "acceleration" of the crankshaft when that cylinder fires. So when ECU measures that there is a difference in rotation speed it adjusts correction factors...
But I could be wrong

[sussexa]

was going down the lines of a service on all 4 before i did the leak back test,
alid1 you have mail.

[sussexa]

looking for best advice now, got 4 spare injectors, car not needed urgently do i?
-try to fit 2 see how it goes and send 4 away for service,then fit all 4
-send the 4 spares away for service and fit (my 4 injectors then spare but knowing 2 are u/s)

and can i recode the ecu for different injectors with fes anyway?

and also i can see how the nozzles may get blocked as can hardly make out the holes at the end they are that small, will try to get a pic at some stage.

http://img534.imageshack.us/img534/3...rnozzle002.jpg

http://img593.imageshack.us/img593/8...rnozzle003.jpg

cant imagine what machine makes these holes?spark eroded maybe.

[losa]

Originally Posted by sussexa

looking for best advice now, got 4 spare injectors, car not needed urgently do i?
-try to fit 2 see how it goes and send 4 away for service,then fit all 4
-send the 4 spares away for service and fit (my 4 injectors then spare but knowing 2 are u/s)

and can i recode the ecu for different injectors with fes anyway?

and also i can see how the nozzles may get blocked as can hardly make out the holes at the end they are that small, will try to get a pic at some stage.

http://img534.imageshack.us/img534/3...rnozzle002.jpg

http://img593.imageshack.us/img593/8...rnozzle003.jpg

cant imagine what machine makes these holes?spark eroded maybe.

If you are sure that these "new" space injectors are OK, fit them instead of those wich you suspect to be defective, and see how it goes.

Or if you are not sure they are OK, get them reconditioned and put them on after that.
My advice is that you let mechanic replace them, because you need new washers/bushes if you don't want any compression leaks, and sometimes old ones can be hard to get out.

And yes, it is possible to record new injector codes with FiatECUScan.

[sussexa]

found a very good diagnostic tool i think for £4.99

http://img194.imageshack.us/img194/5...recordings.jpg

its a boundary microphone that plugs in laptop,googled for free sound type software(i've used something called "audacity")
heres a vid of cold start(sonds like 3 cylinders)
YouTube - injector sound recordings video tailpipe cold start
p.s this smoke stops after a minute or 2(and is just magnified from what ive always had on a cold start but for only a second or 2)

heres a video replay of sound recording of contact on backflow connector elbow in order left to right so 1,2,3,4
YouTube - injector sound recordings video cylinders 1,2,3,4

here are still pictures definately helps to show the differences you can hear but not describe.
i would say the graphs are 1 major injections followed by 3 minor injections(or should be?)

http://img813.imageshack.us/img813/5...recordings.jpg

http://img580.imageshack.us/img580/5...recordings.jpg

http://img97.imageshack.us/img97/506...recordings.jpg

http://img441.imageshack.us/img441/5...recordings.jpg

definately looks like 1 and 3 have cleanest sound graphs(also had least backflow)
looks like 2 has a large second injection, different to all others
looks like 4 has a different graph also to 1 and 3(this had highest bakflow)

will update this again with the same tests when replacement injectors fitted.

[TribesMan]

AFAIK there are up to 3 pilot injections, 1 main injection and 1 post injection on a multi-jet...

[sussexa]

think im wrong, theres no down time between peaks.it looks like that its 1 peak=that cylinder injecting 3 smaller peaks are background noise of the other 3 cylinders injecting(or firing).
so really the major peaks on each set are only what can be compared.
will try to pull 1 peak off each set and put on 1 graph.

[TribesMan]

I think you are right.

Can you try supressing low frequency range? I think that injector sound will be in high frequency range.

[sussexa]

i hope this is 1 cycle
cylinder 1
http://img139.imageshack.us/img139/5...recordings.jpg
you can just make out pre, main and post injections.

cylinder 2
http://img535.imageshack.us/img535/5...recordings.jpg

cylinder 3
http://img522.imageshack.us/img522/5...recordings.jpg

cylinder4
http://img823.imageshack.us/img823/5...recordings.jpg

for the maths peak to peak = 0.14 sec (does this sound right for 800-900rpm)?
duration of injection approx = 0.008 sec?

[losa]

Here you can see order of injection and combustion in one cycle:
JTD (Unijet, always 2 injections)
JTD M-JET and JTDM (Multijet, up to 5 injections)

http://img269.imageshack.us/img269/561/inyeccionx.jpg

[TribesMan]

At 900rpm you have around 15 rotations per second or 30 injections per second (two per each revolution) so thats 0.033s between each cylinder firing. Or 0.133s to repeat firing on the same cylinder.

Injection timing for main injection is around 500 micro seconds at idle. So 0.0005s.
Shortest injections defined in the ECU map (0.5mg/inj - that could be the amount of fuel in the pilot injection at idle) are around 200 micro seconds long.