Faint Knocking/Tapping Noise
07-06-2009, 06:00 PM
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Faint Knocking/Tapping Noise
After a somewhat harder than normal run on Saturday, my truck immediately had a faint knock noise.....almost like a loud tick
It has always ran quiet and this noise just started after the hard run (stupid on my part). I hit about 1300 degrees for maybe 7 seconds
This noise was mainly heard under acceleration, but I also can heard it when the truck is idling.
I have read alot about 03/04 truck dropping valves......would this create a knocking noise?
What can I check or do, before take the truck in to the shop?
I have also heard that a cracked injector will cause a slight knocking noise......
Is the only way to tell if they are bad is by pulling each injector or can they be scanned while in the truck?
Will a cracked injector tip show up on a scan?
I let the truck sit all day Sunday and all day Monday. I just started the truck up and it started fine, ran fine, and idled fine.
The knock, at idle anyways, seems to be more of a constant tap, tap, tap, tap......
The noise started after it was idling for about 10 seconds
Oil level is fine, oil pressure is fine, etc......
Anyone?
It has always ran quiet and this noise just started after the hard run (stupid on my part). I hit about 1300 degrees for maybe 7 seconds
This noise was mainly heard under acceleration, but I also can heard it when the truck is idling.
I have read alot about 03/04 truck dropping valves......would this create a knocking noise?
What can I check or do, before take the truck in to the shop?
I have also heard that a cracked injector will cause a slight knocking noise......
Is the only way to tell if they are bad is by pulling each injector or can they be scanned while in the truck?
Will a cracked injector tip show up on a scan?
I let the truck sit all day Sunday and all day Monday. I just started the truck up and it started fine, ran fine, and idled fine.
The knock, at idle anyways, seems to be more of a constant tap, tap, tap, tap......
The noise started after it was idling for about 10 seconds
Oil level is fine, oil pressure is fine, etc......
Anyone?
07-08-2009, 06:22 AM
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I talked with my local Cummins repair center.
They tech said that it "could" be a stuck injector. He stated they could do a return flow test, which also blocks fuel flow to each injector one at a time.
He said this "may" indicate which cylinder is at fault. It takes about 2-3 hours and the shop rate is $84 per hour. Another option he suggested is to flush the fuel system with BG Products. The shops stated they have had success on other Dodge trucks with similar complaints. Approximate cost for this is $200.
They tech said that it "could" be a stuck injector. He stated they could do a return flow test, which also blocks fuel flow to each injector one at a time.
He said this "may" indicate which cylinder is at fault. It takes about 2-3 hours and the shop rate is $84 per hour. Another option he suggested is to flush the fuel system with BG Products. The shops stated they have had success on other Dodge trucks with similar complaints. Approximate cost for this is $200.
07-15-2009, 05:53 PM
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The Cummins shop had the truck all day today, and said the noise was abnormal.
They did the injector leak down test and scanned the truck, and the injectors are definately not the issue.
The also pulled the valve cover and checked the valves, clearance, etc. They said everything looked fine on the top end
They said the noise has to be on the bottom end of the motor, great!
Tomorrow, they are going to pull the oil pan and inspect the motor from the bottom-up.
He said it might be something like a bearing (dont recall which, maybe he said a rod or journal?)......he said if the bearing(s) are bad, the replacement could still be done with the motor in the truck
Not very pleased, but what I am going to do......oh well
They did the injector leak down test and scanned the truck, and the injectors are definately not the issue.
The also pulled the valve cover and checked the valves, clearance, etc. They said everything looked fine on the top end
They said the noise has to be on the bottom end of the motor, great!
Tomorrow, they are going to pull the oil pan and inspect the motor from the bottom-up.
He said it might be something like a bearing (dont recall which, maybe he said a rod or journal?)......he said if the bearing(s) are bad, the replacement could still be done with the motor in the truck
Not very pleased, but what I am going to do......oh well
07-20-2009, 09:05 PM
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The Cummins shop had the truck all day today, and said the noise was abnormal.
They did the injector leak down test and scanned the truck, and the injectors are definately not the issue.
The also pulled the valve cover and checked the valves, clearance, etc. They said everything looked fine on the top end
They said the noise has to be on the bottom end of the motor, great!
Tomorrow, they are going to pull the oil pan and inspect the motor from the bottom-up.
He said it might be something like a bearing (dont recall which, maybe he said a rod or journal?)......he said if the bearing(s) are bad, the replacement could still be done with the motor in the truck
Not very pleased, but what I am going to do......oh well
They did the injector leak down test and scanned the truck, and the injectors are definately not the issue.
The also pulled the valve cover and checked the valves, clearance, etc. They said everything looked fine on the top end
They said the noise has to be on the bottom end of the motor, great!
Tomorrow, they are going to pull the oil pan and inspect the motor from the bottom-up.
He said it might be something like a bearing (dont recall which, maybe he said a rod or journal?)......he said if the bearing(s) are bad, the replacement could still be done with the motor in the truck
Not very pleased, but what I am going to do......oh well
Last week i took my truck into the dealer about this noise, they replaced #2 injector, checked valve lash and replaced the hi pressure pump. The noise is still there... The tech said 06`s and 07`s have this noise because of the way Mother Mopar mapped the fuel. He said it`s normal, once i get over the slight tapping sound i`ll be in love with this truck.
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07-25-2009, 02:52 PM
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Valve cover was off, and they saw nothing that would be causing the knock.
The oil pan was removed, and they did not find any metal shavings or particles.
The transmission flexplate is also fine, not warped or cracked
They are going to pull the head and see what lurks underneath
As of closing time today, the head is about half off.
The head should be pulled all the way off, by mid-day Monday.......gulp
The oil pan was removed, and they did not find any metal shavings or particles.
The transmission flexplate is also fine, not warped or cracked
They are going to pull the head and see what lurks underneath
As of closing time today, the head is about half off.
The head should be pulled all the way off, by mid-day Monday.......gulp
07-25-2009, 03:59 PM
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Man, sucks to hear about this, how many miles on the motor? At this point in time where they are with all the work they have done to it, i hope they do find something wrong with it. If they do find something wrong, i hope it is covered under the Cummins warranty still. Just hope they dont say, well we cant find anything wrong, here is your bill for $xxxxx amount. That would really be a hard one to swallow. Good luck.
When i had my 06 i had noises from the motor that seemed odd to me, even took it to the dealer to have it checked out but they too said nothing was wrong. Just never really trusted the truck thats why i sold it.
When i had my 06 i had noises from the motor that seemed odd to me, even took it to the dealer to have it checked out but they too said nothing was wrong. Just never really trusted the truck thats why i sold it.
07-26-2009, 02:13 PM
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keep us posted, i have a simailar noise with my 07, dealer said it was fine, i brought it to a shop that shut down all the injectors, everything seemed good, i checked valve lash and all were in spec, ive tried power service in the tank for a month after every fillup. then last week i changed the oil and added 1 quart of lucas stuff thats supposed to quiet things down and prevent dry startups, so far my truck is quieter but still louder when i drove it off the dealer lot.
i am stumped
i am stumped
07-27-2009, 02:47 PM
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Not to be cynical, but..
sound like a classic case of "if ain't broke, don't fix it".
Mine's been ticking since they went to ULSD. It's probably too late in your case, but I'd try to find some LSD (see www.flyingJ.com ) or 10% Bio-D. Quiets mine right down.
Mine's been ticking since they went to ULSD. It's probably too late in your case, but I'd try to find some LSD (see www.flyingJ.com ) or 10% Bio-D. Quiets mine right down.