My N14 Has Gone Through Ten Injectors Within a Year

My last N14 I had a random injector misfire, so I replaced all 6 injectors, pass thru's, wire harness, fuel pump and hoses.
Fixed the problem. I also had the ECM looked at and the software was checked out.

 

Scratching my head on that one my friend but I will put it in for good consideration.

 

No.
Just a hesitation during acceleration. I'm certain was from the injectors as I started replacing parts from the fuel tank.
The last 2 items were the injectors and ECM. ECM checked out good so I replaced all the injectors.

I look at replacing parts as an investment not just an expense.

 

I went through a round of injector failures a while back on an ISM. Same style injectors as yours. If you can find that would be a lot better than me trying to tell you what I learned from some good people on on this forum.
You probably already know RX is rebuilt and PX is new.

 

PX is also rebuilt, just two years warranty instead of 1 for RX

 

If It continues to be in the same holes, then you honestly need to do a few other checks. Make sure you don't have an oil soaked pass thru, and that your wiring between the ecm connector, the pass thru, and between the pass thru and injector are all good.

Someone else mentioned cleaning grounds. Yes. Absolutely. Grounds and power from batteries. Clean then and make sure they are good and tight. I have seen celect and celect plus misfires from crappy batteries and battery connections. These engines, like all electronic cummins engines, absolutely require a clean and healthy 12v.

Clean fuel was also mentioned. also yes. fs1000, keep it changed,keep a spare. also, inspect the ecm cooling plate check valve (will be the line from the ecm plate to the fuel pump) is not full of gunk. even if you have a clean filter, if there's crap past it your injectors are continuously eating it.

Correct adjustment. there's 2 stops in the injector adjustment. the 2nd stop is bottoming the injector out. it's easy to pass the first stop when using a 15/16 wrench. I use a nut driver with a socket to be sure I don't pass that first "stop". back the adjustment screw off 2 flats and tighten.

Finally, quality of cummins recon parts has drastically circled the drain last year or 2. even new parts for certain platforms are questionable. years past, I would have never recommended aftermarket parts for a cummins engine, but now, if a customer wantes to try it I wouldn't blame them. aftermarket parts quality is not my specialty however, and that's a question for someone else on the internet.

Just a thought.

Edit to add: if it's eating all of them, double check gear pump pressure (125 psi), inlet restriction, and air in fuel. I saw you've had a few places already check for air in fuel. You need to also load test the aforementioned wires between the ecm and the injector pass through, not just check resistance. Pass through are notorious for being issues. Also check that you have a good clean 12v directly to the ecm directly from the batteries. Also, the PT switch (fuel shutoff valve) probably needs to not only be checked for resistance and good voltage to it, but also removed and cleaned. Or replaced with the associated nonsense behind it. A good pt switch for a 12v application should be 6 to 15 ohms.

Bud, if this truck were in my shop with a complaint of 10 previous injector failures, I'd be checking it over soup to nuts, junk recon injectors or not. I've attached a picture of the applicable portion of the wiring diagram if you're doing the checks yourself. Definitely would load test all wires with a good light bulb.

Also... hate to say it, but celect plus ecms are getting old and raggedy, and I have been seeing more inj driver issues the older they become. Unswitched battery power at the ecm connector should match your battery voltage at all times. it's ideal to be run directly off the batteries thru a 15 amp fuse.

I wish you luck.

 

Question on passthru's, other than a crack that would allow oil to leak out, how can that part be a problem?

I've changed a few, but I think what you're doing is tightening the wires with the loose "round nuts", when you pull the wire connector thru the hole, and I pin it with a dental pick?

That is why I mentioned the need to check all for tightness.

 

Over time, oil will wick thru the pins, and eventually wick thru the connector into engine harness.

This oil changes the resistance of the wire. With a resistance change, your injector will not be supplied with the proper voltage. This can be as little as damaging to the solenoid over time, to as much as creating a total misfire if the resistance is high enough.

 

He was just repeating something he was told. It’s not true. That’s not how they function.