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copyman
09-26-2013, 07:12 PM
Does anyone what the voltage is suppose to be to the injectors on a 2005 sprinter?
Have a miss and have run test with DAD unit and when # 1 is turned off makes no difference so want to check to see if it is getting proper voltage Check with test light and very low pulse shown on test light.

Aqua Puttana
09-26-2013, 09:25 PM
54722

54723

copyman
09-26-2013, 10:01 PM
Thanks for the reply , still don't know about the voltage to injector if it was 63 volts would have blown test light out. I think I will change the injector and see what happens.

MillionMileSprinter
09-26-2013, 10:05 PM
Holy Crap! 85 times a second AT IDLE!
These truly are amazing machines...

Aqua Puttana
09-26-2013, 10:31 PM
Thanks for the reply , still don't know about the voltage to injector if it was 63 volts would have blown test light out. I think I will change the injector and see what happens.
The info indicates that the switched current is supplied by a capacitor. It mentions what sound like high curents, but they are instantaneous peaks. A test light might be a very heavy draw compared the connected solenoid or a digital multimeter. An incandescent lamp will also appear visually to smooth out the voltage as the filament heats and remains hot during the lows. Your test light (relatively) high load could suppress the voltage.

I wouldn't recommend testing with that light any further. You may screw something up. Stick with digital meters on electronics.

:2cents: vic

Aqua Puttana
09-26-2013, 10:41 PM
...
These truly are amazing machines...
From your mouth to God's ears.

The more I learn about these machines the more I am amazed that there are not more problems. There's lots going on as we mostly cluelessly ramble down the highway.

People complain about LHM, but it really does help to prevent drive train damage while still allowing us to operate the vehicle.

The same goes for the ASR, ABS, ESP lights coming on and being a pain for the operator. If those safety systems go wrong and aren't disabled then they will destroy the drive train.

If I stay with Sprinters my next one will be another T1N. At least by keeping my DAD I will still have some capability of DIY maintenance. Not so much with the NCV3 platforms. Of course money keeps me away from a too new replacement anyway.:bash:

vic

copyman
10-11-2013, 12:58 AM
Changed out # 1 injector with #2 and then did the injector shut down test, # one still has no effect when shut down same as it was before changing position with injectors I now need to figure out the reason # 1 isn't firing.

Eric Experience
10-11-2013, 10:57 AM
Copyman.
Normally if an injector is open cct the ECU will not allow the motor to start so it can not be electrical.Are you saying you where able to start the motor with one injector unplugged?
If not it must be mechanical, like a tight tappet or a hole in a piston. Are you able to do a compression test using a clamp on ammeter? Eric

copyman
10-11-2013, 11:47 AM
No I swapped out the #1 with #2 and then cranked it back up after everything was hooked back up and ran a shut down test with my DAD unit, and still had the same issue with #1 not making a difference when shut off.

Aqua Puttana
10-11-2013, 12:46 PM
The DAD unit provides a cranking test which may show enough relative difference in compression for your needs. Make certain that your battery is up to full charge before running that test.

The DAD provides the injector test which removes signal from individual injectors for CDI3 (NAFTA OM647 engines). That DAD test is not available for the CDI2 (NAFTA OM612 engines) because the engine shuts down when it loses any one injector signal.

The OM612 injector circuit differs from the OM647 control. The OM612 engine will shut down as soon as an injector connector is unplugged. The OM647 engine will run with an injector electrical connector unplugged.

A real world example of an OM647 engine running with one injector disconnected is here.

http://sprinter-source.com/forum/showthread.php?t=25257

To be clear, I am not recommending that anyone run with one injector disconnected. This just shows that a 2005 can/may run with a bad injector circuit connection.

:2cents:
vic

copyman
10-11-2013, 01:41 PM
What is the correct way to check for a bad injector??

Aqua Puttana
10-11-2013, 01:54 PM
What is the correct way to check for a bad injector??
What I would do as a DAD owner.

Perform the DIY injector leak off test.

Use the DAD injector test routine.

Compare the various injected quantities indicated by the DAD to see that they are all within a reasonable range.

That said, you have switched injectors and you indicate the symptoms remain in the #1 position. That hints that the problem is not the injector you swapped over from the #1 position.

I would run the DAD cranking compression test before going any further with injector testing.

:2cents:

vic

Eric Experience
10-12-2013, 11:22 AM
Copy man.
Thanks Vic for the clarification. If you motor does run without an injector plugged in you may have a faulty connection to the ECU.
I have stated a long time ago that a lot of faults are down to bad connections and replacing a component is just an exspensive way of cleaning a contact. I suggest you pull out the injector plug from the ECU. it is the first plug with the heavy wires and about 15 pins. look at he pins and see if they are shiny or dull. If they are dull give the plug and socket a good spray of WD40 and then refit the plug and ECU. Restart the motor and let us know what happened. Eric

copyman
10-13-2013, 12:08 PM
Have pulled the plug from my ECM but the one for the 2005 has 96 pins that goes to the engine and they are all clean and shiny, want to check the harness to the injectors. Does anyone have a description of the pins I believe that #1 injector is pin #73 and #2 injector is pin #25 but would like to see a diagram showing the collation of each pin on the ECM to engine plug

bc339
10-13-2013, 03:01 PM
Which version of DAD do you have? In the diagnostics help section of DAD V5X are the various vehicle systems - under the CDI3 OM647 (as well as each system) are the wiring diagrams that will give you the information.

Bruce

sailquik
10-13-2013, 03:41 PM
Got to agree with Vic here.
If your #1 cylinder is not firing, with 2 different injectors installed, then it's a remote possibility that it's the wiring to the #1 injector, but
a compression test would be what I would do first.
If you have a bad valve or some other compression leak on the #1 cylinder (hole in the piston, bad rings, burnt valves) the injector could
be firing perfectly, but without any compression, the mixture does not compress enough to self-ignite (the basic premise for a diesel engine
to run at all) when the fuel is injected. So, nothing happens and you get a wet stack condition in that cylinder as the fuel is going in, but
there no super hot compressed air to make it burn.
The air must be compressed enough to generate fuel ignition temperature in that cylinder, then when the fuel is injected, it explodes/burns and
you get power.
Did you look in the #1 cylinder when you had the injector out?
If it's wet with fuel in that cylinder, no amount of fooling with the electrical system is going to fix the lack of compression.
Was the #1 injector wet with fuel when you removed it.
Have you spun the engine with the starter and listened for "hisses" in the intake or exhaust tracts...(indicating a bad valve most likely).
Does your engine crank smoothly when you engage the starter, or is there a jump in the rotational speed when it comes up to fire
on the #1 cylinder.
Roger

copyman
10-13-2013, 05:12 PM
When I had the injectors out I did a somewhat crude pressure test that Andy told me about with a rubber plug with a hole drilled in and applied 40lbs of air into #1 with being on top dead center and it blew the plug out, Did the same on #2 with same results, So do not feel that have compression issue. The injectors were not wet when they were pulled, Am trying to find a chart that show the collation to the pins off the ECM, currently reading Sprinter OM647 2.7L Diesel Operation & Diagnosis manual to figure out the pin description.

copyman
10-13-2013, 06:07 PM
Well Just finished test #1 injector plug with ohm meter from pin 73 to plug and pin 1 to plug and #1 injector plug show continuity and did the same for #2 plug between pin #74 and #25 and they show good. So I think that the next step is going to be to change #1 and #2 injectors unless anyone has any other advice?

bc339
10-14-2013, 12:58 AM
Here's the wiring diagram and legend if you still need it.

Bruce

Eric Experience
10-14-2013, 10:37 AM
Copyman
It is clear that it is not an injector problem, so changing them will not help. I am not familiar with the ECU with just one plug. All the ones I have worked on have about 6 small plugs. this enables the engine to be removed with the engine loom still attached to the motor. From earlier post it is clear that the Nafta ECU are totally different to the rest of the world, However the principals must be the same. If you look back into the Ecu with an OHM meter the pins for each injector should look the same. Also you found a cct for both wires to the injector but did you test for a short between them or an earth. Eric.

Aqua Puttana
10-14-2013, 01:40 PM
...I am not familiar with the ECU with just one plug. All the ones I have worked on have about 6 small plugs. this enables the engine to be removed with the engine loom still attached to the motor. ... Eric.
This is what the NAFTA OM647 ECM/ECU looks like. Maybe this infrmation has some value.
55013

55014

55015

55016

55017

Boater
10-14-2013, 03:52 PM
When I had the injectors out I did a somewhat crude pressure test that Andy told me about with a rubber plug with a hole drilled in and applied 40lbs of air

When healthy you should have nearer 40 bar (38 IIRC) per cylinder, with a max variation of 1 bar between any 2 cylinders and min around 28bar
40 psi is about 2 bar, that isn't really going to show you if you have a leak that only opens up at higher pressures and limits the compression in that cylinder....

Check the pressures for your engine - they may differ slightly to mine, but the order of magnitude will be the same.

copyman
10-14-2013, 11:02 PM
Well the fun just gets better and better, Put a spare injector into #1 and then hooked injector externally to the fuel rail and plugged #1 plug in and cranked up and there wasn,t enough fuel spray to say that there was any no Pressure to speak of. Ran for over a minute and only got tea spoon of fuel in jar, looked more like mist instead of spray. I am thinking that the ECM may be bad so does anyone know if and what all I would have to have to change out the ECM with a used one?

Aqua Puttana
10-14-2013, 11:32 PM
You have a DAD.

What is the fuel rail pressure while cranking?

What is the fuel rail pressure while running?

vic

copyman
10-14-2013, 11:40 PM
Fuel rail pressure running is 348 bar 5047 psi

Aqua Puttana
10-14-2013, 11:56 PM
Fuel rail pressure running is 348 bar 5047 psi
Sounds good enough at cranking.

A high(er) resistance short or ground might suppress the #1 injector signal. In another thread someone suggested "floating" the ECM free of its mount to help reveal a grounded sensor. Maybe that is worth a try?

I would think that sending the ECM and SKREEM to SOS Diagnostics would be preferable to messing with a used ECM. I recall that some ECM parameters which are hard coded make direct swaps less than optimal.

My suggestion.

Write down the information you have so far and contact Doktor A or Dennis Lindenengineering for some direction.

Good luck. vic

copyman
10-15-2013, 12:02 AM
Have contacted Doctor A and he told me to contact SOS which I have and will go ahead and follow that route so probably will not be posting much else on it as will have to send ECM and other stuff off to them. Will post results later on.

Eric Experience
10-15-2013, 11:24 AM
Copyman.
A teaspoon full in a minute is the correct amount of fuel, in fact it is more than I would expect. 5 teaspoons full in a minute for the hole motor would be very heavy consumption. Eric