Injector Knock
 

What does it sound like? I have checked my valves and among other things and still at 1800 to 2300 rpms with no real pull I have a knock rattle like metal tapping. I don't want to drop a pile of money changing parts if I can narrow it down. Any help please!:s:

How does it run when you first start it in the morning?? Mileage ok, no fuel in the oil??

no fuel in oil, seems to run fine when I first start. When at low idle it purrs like a kittin when cold and kicks to high idle has a blurp in it but nothing serious. I figured that was just from the 3 cylinder high idle I heard about. No excessive smoke. Just when you get to 1800 it kinda metallic knock. Only when not under load. Going crazy here. Worried something is wrong but don't know what it is and I don't want to just start throwing parts at it. I have never heard a injector knock or rattle so I really have nothing to go off of. Thanks for any help.

Can you turn your high idle off:humm:

no, don't think so, if so I don't know how

Do you think I should recheck the valves, It really sounds like valve rattle:humm:

mine is doing the exact same thing. idk what the hell it is but i say not injectors cuz my injectors are only 2 weeks old and it sounds like we are havin the same issues with the knocking

Thank god someone is with me, it is crazy and driving me nuts. It has my stomach in knots just thinking about it. Gonna pull the valve cover again this weekend, try it cold and try it hot. Anyone know if cold lash is different than hot lash.

id say run some fuel additive and hope like hell that that will fix it. but you also gotta remeber that cummins have a weird "knock" to them anyways so it might just be the way the cards fall

I'm running into the same issue with my truck, but I'm running stacked programmers and it only does it when Its cold..so wtf??:argh:

mine does it at all temps but not all the time it seems. Got me going crazy. Been running Power service, any other additives anyone would suggest.

Ok so its obvious that we both need help from people who work on these truck everday, looking for advice from a sponsor maybe:humm:

i dont work on them every day but from time to time i'll accept a cummins job. my best way to try to help is to ask when did it start?

When I got my custom tunes from diablo sport

Mine has developed a rattle also. I just changed the oil, adjusted the valves, and added a oil bypass filter. The rattle seemed to get lot louder and worse. I can't narrow it down. Afraid my injector/s are going south. I don't know what else to check. Can u get the injectors checked?

you can get them checked. but like i said in my previous post on here. i have got brand new injectors and mine is still doing it

mine started a while ago, maybe 4000mi ago. I don't drive my truck all the time just when I need to haul something or on the weekends. good power no fuel int he oil and no blow, just a knock rattle that makes me crazy:argh:

that is a problem. that is actually exactly what i was thinking. those of you with tunes can ya'll run a stock program?

yeah, I will try that, but I have my smarty on a low setting one stage above stock. Will try the stock setting

Check the injector hold down clamps and make sure thy are tight, especially #4. Injector rattle just seems to get worse with age. Likely it is the spray pattern chaning over time that is causing it.

FYI, just because one has new injectors does not mean they won't rattle. Depending on how the injectors are balanced and setup it may still rattle, custom tips or stock.

OK I tightened the bolts where the blue squares are on all lines, is there any other places I need to tighten?

i've gotten to the point that i don't pay attention to the little knocks and extra sounds. seems like sometimes i have extra noise, and other times i don't. figure i'll run it until something really shows itself as an issue.

I also have an 06 with 88,512 mi on it and mine has tapped since I got it. I have good fuel mileage, no fuel in the oil, I just replaced the clutch and got rid of the dual mass fly wheel, and I had the valves checked. Everything checks out and the truck still does it with no tune. I have heard that the 06 model year tends to have a weird tap but I don't know anybody else with an 06 to compare it to. Its driving me nuts, can anyone confirm that the 06 has any type of difference in the valvetrain setup than any of the previous year CR's?

I am so glad I am not the loan ranger in this. It seems if I hit high RPMs and it is a little cool but the engine is not cold it is really the worst

My '03 had this "problem" about a year ago, try making sure your valves are adjusted properly, I helped mine some but also like what was said earlier cummins have alittle bit of a tapping sound normally. Also does you have any mods? Like programmer or injectors? If so try putting it back to stock and c if you hear a difference.

Mine had the same problem so I took it into my mechanic and he told me it was number 3 and 4 injectors. So I said fix it because it is driving me nuts!!! He told me that he checked them and they were fine but to get rid of the rattle he recommended I try Howes lubricant. I stopped at my local pilot truck stop and picked up a 32oz bottle 4 oz. will treat 30 gallons. I am on my second tank full and rattle is almost completely gone and my truck seems to have more pep. Thanks John!!! NAPA Truck Service Corydon, Indiana. I have a 07 Dodge 3500 with a 5.9 no mods hope this helps.