Hello

I have been told by a mechanic that he believes I have one or more leaking injectors. The 2006 5.9 3500 runs fine but will jerk at light throttle when going downhill with or without cruise control. It doesn't make white smoke or anything like that. It has been slightly slow to start needing 5-7 rotation turn over. I am not looking to add HP or anything like that, but better MPG would be nice. I recently purchased the truck and it has 175,000 miles. I am thinking about pulling the injectors myself. No local diesel shop can test my current injectors.

Questions:

Where is best place to get injectors tested?

Should I replace all of the injectors even if only 1-2 are bad?

If I have bad ones, can I just replace nozzles?

Can I just replace 1-2 nozzles and not all?

Do I need to replace feed tubes?

What experience do you all have with the injectors? Anything I should lookout for?

Thanks in advance.

 

Wow.
Underwhelming response.

Well, I took out my injectors and sent them in for testing. 5 of the 6 were bad. I replaced all 6. I reused my feed tubes and it seems to run well for now, starts faster. 1 of my injectors was wide open leaking. I believe that was the reason for the truck surging / bucking when coasting or at light throttle. The surging / bucking was fixed by injector replacement. Another symptom I had was when the motor was revved greater than 2000 RPM's, it would not idle back down - it would just continue revving between 2000-2500 RPM's on its own. This was also fixed by injector replacement.
I now have a boost leak at the grid heater. I should have bought 2 new gaskets to prevent this before starting the job, but this is relatively easy to fix.

 

Im glad you got it fixed. If you run a chip. Remove it. It will wear out your injectors quicker. Also in your engine the injectors are nozzles. Also the jumper tubes are crush seal, so you probably should have replaced them, I hope you have good luck.

 

No chip.
I did quite a bit of internet searching regarding the feed tubes and possibility of reuse. I found many claiming they reused the feed tubes, some multiple times with success. I examined the feed tubes and they looked good so sanded with 600 then 1500 grit, cleaned and reinstalled them. They seem to be working properly now as the truck starts right up and runs well.
I have been advised the factory fuel filtration is woefully inadequate for the pump and injectors in these trucks. I have an aftermarket 2 stage fuel filter system which is next for installation.

 

Who advises you of the woefull fuel filter problem? I have the stock upgrade and change I every 10k and it has been trouble free. Just curious john

 

I have read many opinions posted on boards such as this that the stock filtration is inadequate.
I bought one of these:
http://www.dieselpowerproducts.com/p...e-cummins.aspx
If you read the description, it describes the purported benefits of increased filtration. Don't want to believe the company advertising its product? How about the guy who rebuilds injectors? The guy who tested my injectors (and sold me rebuilt ones) told me the stock filtration was woefully inadequate. I had my injectors tested here:
http://www.accuratediesel.com/

 

Thanks for the info. How much are injectors?
Jb

 

The good guy at Accurate diesel charged me $30 each to test my old injectors, and cut that to $15 each when I purchased reman injectors through him. He sells Dtech reman injectors for my 06 5.9 with 1 year unlimited mile warranty for $235 each.

 

Thanks for the heads up...did you say that you had 175000 miles on your truck? How long, if maintained will injectors last? I change my oil every 5k. I recently bought the truck, it has 116000 miles. It runs great.
Other little crap bugs me, but the engine is solid.
I have had to get the sunroof flashed so it fits properly, but it still allows condensation in because the windows fog up, but at least I cleaned the sunroof drains so if it does leak it drains. Passenger power seat does not work. Luckily it doesnt have to. Gear shifter sometimes does not show park, so cable needs adjusting. It seems like the little things begin to add up.
JB

 

John

I wish I could answer the question regarding injector longevity. I have read some posts advising against ever buying a reman injector with lifespan from failure before getting out of the garage after replacement to 200k miles. I am sold however on increased fuel filtration as cheap insurance to protect expensive components.
I just bought my truck with 175k miles or so and it needed the injector job when I bought it. I had 1 shop quote me $6,000 for the job and he wasn't even a dealer. I did it myself in about 4-5 hours to remove and 4-5 hours to replace having never done it before. In all it cost me around $1,500. Running my VIN number it lists 1 injector was replaced at around 115,000 miles. More may have been replaced and not reported against my VIN - like my injector replacement last week.