I have a terrible knocking noise at idle, and my dealership dosen't know what it is. They have changed my injection pump gear and they said that that would fix it, but it hasen't. Any ideas?

 

Most likely a bad injector.

 

Had mine in the dealership for probably the same kind of knock yours is having. They told me it was normal, just drive it. Yeah Right ! !

I got tired of listening to it and took someones advice on here over the weekend and went to Auto Zone and bought a bottle of Lucas injector cleaner.

I'm not going to get up on a soap box here, but after pouring this stuff in and filling up with diesel, I was amazed at how it tamed it down ....... didn't fix it ........ but made it less annoying. For a whole $3.50, might give that a try.

 

the dealer is saying the knocking is from dirty injectors.(well on mine anyways) and wants $150 to clean them. I told him to get bent that a truck with 48000km should not have dirty injectors. and if it did then it should be covered under my warrenty, as it isnt part of scheduled maintenance at this time, needless to say he didnt say anything after that.

 

See im in a bit of a diffrent boat, i dont have a knock. But mine smokes like nothing. black smoke at that. If ive been driving a while i can really poor it out and mines stock! nwo if i go from light to light and romp it, it wont do it. Or sometimes i get some white smokke. back in the day it was usually just a timming issue, i didnt think i would need to worry on this truckk. Ive had the update for the mileage white smoke and so on. never use to do it. but now shes so bad i have to wash my truckk every couple days to get the soot off

 

I Have 56000 on my truck now they did the injector cleaner on it at 50000 and it quited down for a few days. I just wish i could get rid of it! it get real annoying when i am idleing for a few min. They have told me it could possaly be the #3 injector and they were going to replace it but that was in early Feb. (I am really ****** at the service shop abit that.) they tell me they are on national backorder. I think they are full Of IT.

 

I have had mine in for the injector knock several times the last time they said it was fixed and the cause was carbon bildup on the injectors. I noticed when I got home that there was a note at the bottome of the repair order that stated I had to pay for all services in the futer that delt with engine noise. They said it was my fault that the injectors are carboned up and I dident work it hard enough to keep it clean. I abought had a fit. I told them that for $40,000 they had better desighn a truck that can be driven daily between pulling huge loads. If all this thing is good for is strictly towing I was going to trade it for a Duramax. They dident say much. To me it is a design problem. With as many of us as there are complaining abought it, its not just the drivers fault, something is wrong. Withought a dought this is my last Chrysler product. I have never been givven the run around on so many stupid little things. I realize that every brand has its problems but D.C. customer servise is a joke along with its warenty. I am seriously considering bombing the truck just so there is no warenty to wory and complain abought. Not that there is much diference between the current full warenty and NONE but I mite a well have the extra power to go along with the headaches of dealing with Star.

 

I don't know what it is about the 3rd Gens that generate so much carbon build-up in such a short period of time, but that will account for probably 75% of knocking problems that you hear about on the forum. I recently had mine out for an upgrade and with only 15,000 miles on them, the carbon build-up was so thick I could break it off in chunks with my fingers. Being in Alaska I'll be the first to admit my truck idles much more than it should, especially in the winter, but to be as bad as they were in only 15,000 miles was very surprising. I have used a fuel additive of some variety in every tank since new. Lots of short trips are a no-no. Idling for more than 2 or 3 minutes is a no-no. These engines really need to be brought up to temp quickly and worked hard to stay clean and healthy.

 

My truck also knocks at idle, but with a little Power Serve Diesel clean at every fuel or Stanadyne Performance formula, which also works, seems to clear up the knock and it idles much smoother.

You might want to give it a try.

Blair

 

Took Dad's 03 with 44,000 miles in to a local dealership in Colo Springs. 85$ later dealer tech recommended a TSB update and fuel additive for $135 more. I told him it's not a fuel quality issue since I have been running Power Service every fill up and it had run fine without the TSB before it developed the knock. Took truck back in the next morning and demanded a injector cutoff test be done and engine power balance test which I got from people here. Picked the truck later that day and guess what four bad injectors Now, I have to wait until STAR authorizes the injector replacement which they said will take a week

Joe

 

You cannot perform the cylinder balance test on an 03, only an injector kill which means that they were "hittin and missin" on their diag. Probably hoping to replace enough injectors to hopefully change the noise and make you happy. As far as the carbon build up, it's always been present. You can ask all the way back to first gen guys that have added fuel conditioner and waalaa!! the engine seemed quieter. It's just with the "quiet" technology it's easier to pick up on. Even on my 01 from time to time in gear at idle you can hear a bit of noise. Usually after a couple of tanks with Power Service and it will quiet out. Most likely the new engine is more sensitive to the carbon obstructing the fuel spray, which is creating larger "droplets" of fuel which is giving you that old school "crack!" when it ignites.

 

My 03 is used for short slow trips every day, I do use Power Service every
fill up, I do notice a change in engine noise if I don't. When she starts
getting a little knocky and sluggish I take her out and run 90 mph for
10 miles or so, I do notice a much more quiet idle and better acceleration
after that, I guess its blowing some of the carbon off ?? My first diesel.

HOPE I'M NOT SCREWING UP BY DOING THIS..??.....

 

Mine gets noisey on poor quality fuel (less mpg). More mpg better quality fuel and quieter. Add lubricity factor (10W non-detergent low/no ash oil) to fuel and mpg is up and quiet. Increase cetane without lubricity/density and noisey again.

Think there might be something to the myth about poor quality fuel. I know the HPCR is much more sensitive to fuel quality that those that have came before.

 

I agree with AaronT,, Poor fuel really knocks the pee out of the power on my
3RD GEN. If I were pulling for a living I guess I would have to spend all
the bucks for all these boxes & re tuners & intakes & exausts & gauges &
Injectors & doo dads so I could pull the load if I got winter blend or bad
fuel. What do the big rigs do ???...