Recently I've noticed that my motor has a definitive knocking or detonation sound when accelerating. As I'm rowing through the gears either lightly or heavly accelerating, I notice this intermittent knocking sound. It sounds like a gasser that needs higher octane fuel....detonation for a lack of other descriptive words. It doesn't do it all of the time, matter of fact it seems to come and go. When the sound is not present the truck seems to be running at it's best. But when it does do it, it also seems down on power when the noise is most noticable. Some days the motor is a quiet as could be, others it sounds like my old 2001 24 valve??? I read before that some folks claimed it was an injector problem, or a problem with the "pre-squirt" of fuel. Has anyone fingered this noise and what was the cause/fix?

 

Sounds like you may have an injector problem. One bad injector seems to give you that knocking sound. Do a search....

 

Also try to remember if it is when you get fuel from certain places. It may be the fuel quality, Check you fuel filter, have you ever changed it and how many miles on it?
Answer these questions to get part of the answer yo need to complete your quest for an pinging knock question.

 

I noticed my less then one month old 04.4 2500 seemed to rattle a little when new but it now occasionally blows blue smoke on cold starts, idles rough, seems to mis-fire and getting erratic and less then claimed MPG (6.5 to 12 city) and 12 to 14.5 highway at 70mph or less. I now notice what sounds like a fuel knock at idle and power seems less then new, now at only 2000miles.. 0 to 60 seems to be 10.5 seconds and was closer to 8.5 when new.

I have been reading other posts about injector problems and even a CTD that self-destructed due to an apparently stuck injector After owning a few diesels and experiencing some injector problems I would guess that many 04’ Cummins 600’s are experiencing some sort of injector problems. Rig is going in next week for a check but I would feel better if I had a whole new set of injectors.

Btw, does anyone know if it is possible to flow check or bench check the new 600 injectors?

 

I replace my fuel filter every oil change (8000 miles) just to be safe. I also use the same fuel station which has always done right by me in the past. I took it to the dealer on the way home yesterday for another problem and told him about the knocking. He seemed to think the lift pump was going bad since the injectors were just replaced ~5000 miles ago. I was telling him how sometimes the motor seems down on power, coincedently it's down most when the knocking is at its worst....hence why he thinks the lift pump is taking a poop. Isn't the lift pump under warranty for 100k miles like the motor? Unfortunatley this is a "country" dealer that doens't have an in-house diesel mechanic, so back to the city it goes next week. I will say one thing about this place, they fix crap the first time, not this "we can't duplicate the problem" crap I hear from the soposed 5 star one in the city!

 

Update on my problems. The other day the "water in fuel" light came on. I drained a lot of water out and now the motor seems to be more quiet and running better....talking about eating my words about my fueling station doing me right! Wednesday is goes in for the crazy A/C and the "about to fall out" U joints.

 

My Knocking, smoking and rough running 04.5 Cummins 600 just spent the day at the shop.. As I expected they said that without any computer codes or being able to duplicate the rough idle or blue smoke they cannot act.

Service manager said what I described was unheard of and they have had “0” problems with the 04’ Cummins… I showed him about a dozen posts of people having the same problem and even the one about the 03’ that self-destructed due to a stuck injector and did not show any codes. He said the injector was unlikely so I played him the clip of the one person’s CTD before and after the injector replacement, mine sounds worse but he said that Dodge will not act on data obtained from a website so basically pointless information.

Bottom line is that Dodge will not remove, inspect or replace an injector for noise, questionable performance, rough running or a low mpg.. Sort of confirms my assumption that warranties are more a marketing ploy then a guaranty of service or protection..

As for the pronounced “knock” and “pinging” rattle I could not seem to get them to even respond to that issue other then “it is normal”, However that knocking has recently become just as pronounced in drive as in neutral and on light acceleration it is starting to occasionally sound like a “Rod Knock I listened to another almost identical truck with 8,000 miles that produced no Knocking or pinging at all.

Fuel Economy is still around 8mpg to 10mpg in town and 65mph steady state mpg by the computer on level ground, no wind 14 to 15.2mpg.. Filled up a couple of nights ago and spoke with a new owner of a ram 3500 dulley, who just bought it in southern CA . Even with an oversized camper and Wells Cargo trailer his second fill-up produced 13 mpg after pulling the pass into southern Oregon at 60 + mph.

They did say that mine is within the range for a PCM Flash update but I am hesitant to have it performed until the other issues are resolved.

I would be interested if anyone else has a similar story?

 

04 2500 4x4 , 305/555, 17800 miles

I've noticed an engine knock from around 700-1500 rpms, at idle and coming off stop sign. Took truck into Dealer on Monday. Yeah, it sounded like a piston was coming thru the engine or a burn't valve. I tried running some Rotella DFA thru a couple of tanks of fuel and no help. Dealer states #3 Injector is bad and is going to be replaced today. I also asked about the door gasket TSB's, and dealer actually thanked me for telling them about the TSB. They've been realigning the doors on trucks to stop the rubbing.. So, the gaskets are getting replaced too.

Now, if I can only keep the 31570r17's from throwing rocks up under the truck

 

New number 3 injector installed and truck back running like a champ! No more knock, when warm, below 1500 rpms.

Now, just waiting for the new front door moldings under the TSB to come in!

 

Glad to hear that...

I was interested to know if the build date for yoru vehicle. my door sticker says: 01/04 and I was told the january vehicles are subject to a TSB for rough running, smoke and flash update and would be interested if those who are having injector problems might happen to be early models?

 

I'll have to go look...I bought it Oct 2003 as the 04's we're coming out, so I presume the build date is JUL-AUG 03. I believe the 01/04 vehicles are the 600 hp engine...I have the 305/555 engine....