Engine knocking slightly at idle on 2005?

[J.Davy]

There seems to be a slight knock at idle that I think has developed over the past few days,nothing to serious just sounds a little more like a diesel than it did new. Power seems to be close to the same but my boost is down 4-5 psi compared to new. Any help would be appreciated. We had a cold snap here for a week. The truck has about 1600 miles on it. Do these electronic wastegate controlers losen up after a little bit?

 

[J.Davy]

Just went by the dealer so they could hear the noise said it was the #1 injector was dirty from idleing to much,they have to pull injector out and soak it. I always high idle my truck so what gives?I have also been using Howes additive as well. I never had a problem with my 03.

 

[sick_ram]

You should have kept your 03

 

[J.Davy]

I am slowly starting to think that.

 

[barbwire]

Their diagnosis doesn't seem right to me. Why would your boost be lower, just because you have one bad injector? Keep us posted, OK.

 

[JHardwick]

Their diagnosis doesn't seem right to me. Why would your boost be lower, just because you have one bad injector? Keep us posted, OK.

From what I know(which may be nothing) fuel=boost. If one (1) cylinder is down on fuel, overall boost will be down as well.

 

[Guzzi]

There seems to be a slight knock at idle that I think has developed over the past few days,nothing to serious just sounds a little more like a diesel than it did new. Power seems to be close to the same but my boost is down 4-5 psi compared to new. Any help would be appreciated. We had a cold snap here for a week. The truck has about 1600 miles on it. Do these electronic wastegate controlers losen up after a little bit?

My 2005 QC, SWB 2wd Laramie Automatic has the exact same symptoms. I now have 2000 miles on it, and last night the neighbor came over after I came home and was letting the truck set and idle for a couple of minutes. He said, "Boy the new truck sure is noiser than the 2003 you had. It sounds like an old diesel with a bad rod!!!" This confirmed what I thought I had been hearing since day one. Went to the local dealer, and told him the symptoms. The service manager said they had a couple of bad injectors on the 2005 models so far, and to bring the truck in on monday for a complete checkup. The exhaust note on the 2005 is also different than my old 2003. I figure that the addition of the CAT has made the difference. At least on my 2005 the downpipe is a full 4", up from my 2003's 3 1/2" downpipe. Seems like the truck is slower than my old truck also; however it is nowhere broken in. Since we have an accellerometer, I will check this theory out shortly. Normally, from a dry start, the 2003 automatic would run a 15. 5/ 89mph in the quarter. Pretty damn good for a stock truck with only the AFE setup. Will post any findings by the dealer next week. GUZZI

 

[juicedcummins]

Sounds like they are trying to make you feel bad for a faulty injector. I just did an oil change on mine to go to 10/30 for the cold months and get the breaki-in oil out. This oil change had 125hrs and 2200 miles on it with no bad knock or wash down in the pan. If this truck is not idling it is run hard.

 

[J.Davy]

They say it is just the pilot injection that is not working so that would explain the noise but I am still not sure on the low boost. I am pretty sure it is not the intercooler I guess if the injector was not working at all that would explain it as well. You can feel a knock on the injector line that I am assuming is at fault.

 

[MLimpert]

My truck consistantly makes less boost when it is extremely cold. Temps in the upper 30s and higher will bring the boost back to normal on mine.

 

[sick_ram]

Thats weird colder air should make more boost. My truck loves the winter. A 80 degree day it makes 25 psi and at 30 degrees is makes about 30 psi

 

[J.Davy]

Maybe it is because it is computer controlled and figures it does not need as much boost in the cold dense air to produce the same power as when it is hot out,not sure just a guess.