With Cummins codes 1139, 1142, 1144, 1143, and 1141. This truck originally came in because it was putting coolant in the fuel. After diagnosing we found the injector cups were leaking. We purchased and installed an aftermarket cup kit. This corrected are coolant in fuel issues but we have been getting these codes since installing. These codes were not present prior to installation. We have checked fuel restriction per Insite and see no issues there. We also removed and replaced the fuel supply tubes to each injector since we could not confirm they were put back with their original injectors when cup kit was installed. Any information or ideas would be appreciated. Thanks in advance.
(08-14-2023 )watkinstt Wrote: [ -> ]With Cummins codes 1139, 1142, 1144, 1143, and 1141. This truck originally came in because it was putting coolant in the fuel. After diagnosing we found the injector cups were leaking. We purchased and installed an aftermarket cup kit. This corrected are coolant in fuel issues but we have been getting these codes since installing. These codes were not present prior to installation. We have checked fuel restriction per Insite and see no issues there. We also removed and replaced the fuel supply tubes to each injector since we could not confirm they were put back with their original injectors when cup kit was installed. Any information or ideas would be appreciated. Thanks in advance.
Did anyone bother to do a proper rail leak-down test after putting it all back together?.
Any time you remove injectors and replace things on a common rail, after you get all the air out of the lines ... you need to do this test before calling it good. It has to be done EXACTLY LIKE THIS VIDEO SHOWS!!!.. AT 30,000 PSI!!!. and not just at idle pressures.
ref:
http://rawze.com/forums/showthread.php?t...3#pid75483
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Also.. the engine uses the exhaust gas pressure sensor to detect injector problems. If that little crossover tube from the manifold to the bottom of the thermostat housing has gotten cracked, leaks, etc... then it will not be able to detect injectors properly, or may give ghost injectors or mis-fire faults. As well, the passageway inside the thermostat housing likes to clog up with soot over time, making the exh. pressure sensor not read correctly.
Engine off and cooled off .. remove the exhaust pressure sensor at the top of the thermostat housing and spray a liberal amount of brake cleaner into the hole.. see if it pools up. If it does, then the circuit needs to be cleaned out.
If the engine has a de-mandate program in it (deleted) then copy the file out of the ecm and e-mail it to me. It is common for those delete programs to disable or partially disable the exhaust pressure sensor, an d later down the road.. you can get random or sudden injector issues like you describe when the injector manager in the ecm is getting nothing but random or half-disabled data.
Thanks for all the information. We put the truck through leakage test exactly how video shows. It failed to pass. Replaced the pressure relief valve on the end of the rail and truck still wouldn't pass.
Capped off each individual injector at the rail and truck still wouldn't pass leakage test. Next step is high pressure fuel pump from what I read in the other post...correct? During all of the running of the engine and testing the codes have not returned. The truck is original equipment and is not de-mandated. Thank you in advance.
(08-22-2023 )watkinstt Wrote: [ -> ]Thanks for all the information. We put the truck through leakage test exactly how video shows. It failed to pass. Replaced the pressure relief valve on the end of the rail and truck still wouldn't pass.
Capped off each individual injector at the rail and truck still wouldn't pass leakage test. Next step is high pressure fuel pump from what I read in the other post...correct? During all of the running of the engine and testing the codes have not returned. The truck is original equipment and is not de-mandated. Thank you in advance.
By each individual injector do you mean one at the time? Asking because it’s common for more than one injector to cause this at the same time.
Yes they were capped one at a time.
(08-24-2023 )watkinstt Wrote: [ -> ]Yes they were capped one at a time.
Typically I cap off 3 at a time. It’s easier to pinpoint where the issue is that way.
After capping off three injectors at a time, truck still fails the leak down test as shown in video.
Any suggestions on where to go from here? I will state the injector codes have not returned during testing.
Well which injectors failed? The purpose of the test is to cap them and isolate which one or ones are leaking.
For instance...... if you cap the front 3 and it still fails, then it's one or more of the back three. If you then cap the back 3 and it fails, it's also one or more of the front 3. Then you can cap off 2,4,6 and run it again, you understand what I'm saying?
If they are all leaking, I would suspect someone didn't torque the feed tubes properly or you have a leak somewhere else like the pump or relief valve.
No matter which injectors were capped the truck failed test. they were capped front three, then rear three, and then all possible combinations of three at a time. 1,2,4 then 1,2,5 then 1,2,6 for example and continued throughout the rest. Alread changed the relief valve. So, it appears I must have a pump issue then.