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Discussion Starter #1
The truck drove into the shop with the driver complaining of engine missing and not pulling properly.
The next day I tried starting the engine to see whats the probelm but truck failed to start
Hooked insite and there were no active codes, engine runs with starting fluid.

Checked unswitched power and ignition power, checked harness to injectors, checked engine position sensor and wires- everything ok
tested the ecm on another truck and it is working fine

Need some help here friends

Thanks
 

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possible fuel feed issue?fuel pressure check first.try to run engine from a bucket of fuel (bypass fuel tanks)maybe something stuck in tank pick up tube.:)
 

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Discussion Starter #3
possible fuel feed issue?fuel pressure check first.try to run engine from a bucket of fuel (bypass fuel tanks)maybe something stuck in tank pick up tube.:)
I installed guage on pressure tap and cranking at 20psi
When I run on starting fluid pressure goes to 120psi
 

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if you're running it on starting fluid then you're bypassing the fuel system by putting the ether in the engine through the intake and not the injectors. either do what quality truck said and run it off a bucket of fuel or take the return fuel line off and see if youre getting fuel through the head
 

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Discussion Starter #5
if you're running it on starting fluid then you're bypassing the fuel system by putting the ether in the engine through the intake and not the injectors. either do what quality truck said and run it off a bucket of fuel or take the return fuel line off and see if youre getting fuel through the head
I am getting fuel from the return line from the head but what I noticed is that the return from the head is linked with the supply line to the fuel pump.
Should be any check valve out of the head return line
 

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If you not geting more than 20 psi at cranking and its cranking fast enough then change the fuel filter first and after bleeding it out and still geting only 20 psi then pull pump and replace or repair.The pressure regulator may be sticking open in the fuel pump or sucking air inside of the pump. This needs to be done with a bucket of fuel connected to the pump by/passing the ecm cooling base plate.Air will cause low fuel pressure but so will a bad fuel pump.You need the manual says 25 psi to start but all the engine i have checked will have 50 psi as soon as it starts and then to 100 real fast.
 

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An M11 needs 195 RPM cranking to start, it should have at least 75 lbs, going quickly to minimum 140, fuel preasure, you want to test the fuel system while cranking for restriction, filter, fuel lines, ECM cooler plate, as will a plugged suction tube, all will give you a high resistance above 10 is a problem, with a new filter, 6 is max.
As with every engine the first things you want to do is clean the battery cables and the grounds. That is something that will not bring a code, it is not as impressive work as the rest it just is what is needed, separate the batteries and charge them independently with a regulated charger, and test them independently.
Check the voltage at the solinoid you must have 9.6 volts while cranking, if you take off the wire the solinoid should have 7 to 8 ohms. Also the wire on the solinoid, will break inside the shrink tube and be hard to spot, giving an intermittent connection, 10 lb tug test it.
Just a thought!
 
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Discussion Starter #8
Thanks gentlemen for your advice, I will work on it today and let you know how it goes.
Does anyone know what voltage goes to the injectors while cranking because I am hearing the solenoids closing but voltage measured is just about 2VDC with a digital multimeter
 

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I have never seen a Cummins have a problem with the ECM, if you are getting power to the fuel solinoid, and 195 cranking speed. You might want to check the wiring plug in the intake cover, is tight
If you have it on the computer and it should show the cranking speed.
 

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Discussion Starter #10
I found no 2 injector spring broken and seals damaged, will replace all injector seals and broken spring and see what happens
 

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If you call Cummins you can for a lot of the Cummins injectors, just buy a spring. You will need the serial and CPL. If the injectors were working there is no reason to replace them all. That is what I called diagnosis by the ripping and tearing method. It is very expensive
 
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Discussion Starter #12
If you call Cummins you can for a lot of the Cummins injectors, just buy a spring. You will need the serial and CPL. If the injectors were working there is no reason to replace them all. That is what I called diagnosis by the ripping and tearing method. It is very expensive
John I will only replace seals on injectors and broken spring.

Would let you know the results
 

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Discussion Starter #13
UPDATE

Started the engine today but it is missing on 3 cylinders: 1,2 & 6. Swap injectors to confirm that injectors are defective.
 

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Discussion Starter #14
Finally replaced 3 injectors and seals and the engine now works fine

Thanks for your contribution gentlemen
 
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