Troubleshooting Clatter, knock and engine damage.
11-17-2004, 12:58 PM
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Troubleshooting Clatter, knock and engine damage.
I was reading threads on clatter and knocking and hoped my experience with bad injectors and various odd sounds like knocking and clatter might help others detect and remedy possible injector problems.
If you listen or drive other similar new and used Cummins engines with the common rail fuel injection systems you will likely notice the difference in smoothness, power, noise and fuel economy. Unless you have some experience and a trained ear you likely will not know your vehicle has an injector problem, and you can’t count on a Dodge service department to know either. MOST SERVICE DEPARTMENTS SEEM TO HAVE LITTLE EXPERENCE AND UNDERSTANDING OF HOW TO DIAGNOISE OR REPAIR THESE FUEL INJECTION SYSTEMS, OR WHAT A NORMAL OR ABNORMAL ENGINE RUNS OR SOUNDS LIKE, OR EVEN HOW TO TEST FOR A DEFECTIVE INJECTOR OR FUEL PUMP..
A leaking or failed fuel injector will cause increased noise, decreased performance and can damage your engine…
I have owned 7 diesel vehicles including a 2001 GM Duramax, and two Ford Powerstrokes. I have worked for a company that operated and maintained over 1500 light duty diesel trucks and dozens of diesel generators. I am familiar with diesel engines, and what is normal for them and what is not. I have also developed engine monitoring equipment for piston engine aircraft and have some knowledge of combustion in reciprocating engines, both gasoline and diesel.
I recently traded my 99’ Powerstroke with 100,000 miles for a new 2004.5 Quad cab short box with the Cummins 600, build date 01-04’. Within two days I began to notice what seemed to be an unusual amount of clatter and knocking. Because of the sharpness and loudness and uneven nature of this knocking sound guessed that at least two or three injectors were leaking (internally out the tip, and not around the fitting that connects the HP fuel line to the injector as some apparently believe constitutes a leaking injector).
It took four visits to three different dealers before I found one (the selling dealer) who would even look at the truck and knew how to properly test for a defective injector, and then only after I experienced what would seem to be a HYDRO LOCK ON STARTUP, and the vehicle was knocking loudly and obviously not producing power on one cylinder, apparently not knowing what constitutes engine miss, knock in a diesel engine or how to test for a defective injector, doing only a simple scan for error codes in the PCM.
To date, in only 8,000 miles I have had three injectors replaced and apparently just experienced a fourth. All failures have basically produced the same symptoms such as, pronounced pinging, clatter, what sounds like a lifter clacking and excessive smoke on cold start that often lasts for minutes, typically worst after setting for 10 to 20 hours and the leaking injector or injectors leak fuel into the combustion chambers. It seems if my vehicle sets for more then 24 hours the pressure bleeds off and enough fuel must drain past the rings and into the crankcase so little smoking usually results.
As the injectors get worse and finally fail completely knocking, clatter and smoking on start-up gets worse. Clatter that starts out as sounding something like Gasoline engine detonation or “Ping”, develops into a lower knock that sounds more like Pre-ignition, piston slap or rod knock as the injectors leak more and deliver too much fuel too soon, especially noticeable on light to moderate acceleration or shifting.
If I let off completely on the throttle, coast for a second and then open the throttle part way and rapidly I can hear a distinct Rattling and knocking that is not apparent after the leaky injectors were replaced.
After the last two injectors were replaced and a fresh oil change at 6,000 miles for about three days and 500 miles the engine ran smooth and quiet on start-up or when at operating temp. Engine clatter or “ping” was practically unnoticeable at any speed. A pronounced knock on one cylinder that started after the possible hydro-lock event when the vehicle had 500miles has remained despite the injector replacements and is noticeable most of the time but I suspect is due to engine damage caused by a badly leaking injector and not the current failing injector.
From what I have observed, when all injectors are operating perfectly there is little or no clatter, or knock and little or no smoke on startup, or when under load, but when one or more start to fail clatter, becomes knocking and associated smoking, idle becomes rough, power is reduced and fuel burn goes up. .
My suggestion is that if you notice any of the symptoms I note, or you suspect an injector problem with your vehicle that you insist on having it properly tested by a technician that knows how what to look and listen for, and how to troubleshoot the new common rail fuel injection problems. The technician needs to understand that the Engine PCM does not seem to be able to detect a leaking injector…
An “Engine power balance test” seems to be pretty effective in finding erratic, plugged or leaking injectors, but the tech needs to know what to look for, if the tech is not experience and/or does not understand the test and just performs it as the manual recommends, he likely will miss a bad injector. After my first injector failed completely the PCM showed no misfire or electrical fault codes, and the second dealer missed it on the Power Balance test.
From new, My engine obviously had a problem as it started knocking severely and missing on one cylinder, but after the first injector failed only a Cylinder Power Balance test showed one failed injector. The power balance test also reveled three more injectors were producing more then a normall %100 power but erritacally between 107% to 118%. Shutting off the leaking injectors during the Power balance test also stopped or greatly reduced the idle knock. Turning off normal cylinders produced little or no change in noise.
Both the tech and myself guessed that the only way those other cylinders could be delivering more power then normal was for more fuel then normal being delivered by (leaking) fuel injectors. STAR however would not replace the injectors as it seems they only replace injectors that are making less then 90% power or failed completely Oddly enough the injectors that were producing more then 100% power were also the ones that later failed or leaked severely.
If you listen or drive other similar new and used Cummins engines with the common rail fuel injection systems you will likely notice the difference in smoothness, power, noise and fuel economy. Unless you have some experience and a trained ear you likely will not know your vehicle has an injector problem, and you can’t count on a Dodge service department to know either. MOST SERVICE DEPARTMENTS SEEM TO HAVE LITTLE EXPERENCE AND UNDERSTANDING OF HOW TO DIAGNOISE OR REPAIR THESE FUEL INJECTION SYSTEMS, OR WHAT A NORMAL OR ABNORMAL ENGINE RUNS OR SOUNDS LIKE, OR EVEN HOW TO TEST FOR A DEFECTIVE INJECTOR OR FUEL PUMP..
A leaking or failed fuel injector will cause increased noise, decreased performance and can damage your engine…
I have owned 7 diesel vehicles including a 2001 GM Duramax, and two Ford Powerstrokes. I have worked for a company that operated and maintained over 1500 light duty diesel trucks and dozens of diesel generators. I am familiar with diesel engines, and what is normal for them and what is not. I have also developed engine monitoring equipment for piston engine aircraft and have some knowledge of combustion in reciprocating engines, both gasoline and diesel.
I recently traded my 99’ Powerstroke with 100,000 miles for a new 2004.5 Quad cab short box with the Cummins 600, build date 01-04’. Within two days I began to notice what seemed to be an unusual amount of clatter and knocking. Because of the sharpness and loudness and uneven nature of this knocking sound guessed that at least two or three injectors were leaking (internally out the tip, and not around the fitting that connects the HP fuel line to the injector as some apparently believe constitutes a leaking injector).
It took four visits to three different dealers before I found one (the selling dealer) who would even look at the truck and knew how to properly test for a defective injector, and then only after I experienced what would seem to be a HYDRO LOCK ON STARTUP, and the vehicle was knocking loudly and obviously not producing power on one cylinder, apparently not knowing what constitutes engine miss, knock in a diesel engine or how to test for a defective injector, doing only a simple scan for error codes in the PCM.
To date, in only 8,000 miles I have had three injectors replaced and apparently just experienced a fourth. All failures have basically produced the same symptoms such as, pronounced pinging, clatter, what sounds like a lifter clacking and excessive smoke on cold start that often lasts for minutes, typically worst after setting for 10 to 20 hours and the leaking injector or injectors leak fuel into the combustion chambers. It seems if my vehicle sets for more then 24 hours the pressure bleeds off and enough fuel must drain past the rings and into the crankcase so little smoking usually results.
As the injectors get worse and finally fail completely knocking, clatter and smoking on start-up gets worse. Clatter that starts out as sounding something like Gasoline engine detonation or “Ping”, develops into a lower knock that sounds more like Pre-ignition, piston slap or rod knock as the injectors leak more and deliver too much fuel too soon, especially noticeable on light to moderate acceleration or shifting.
If I let off completely on the throttle, coast for a second and then open the throttle part way and rapidly I can hear a distinct Rattling and knocking that is not apparent after the leaky injectors were replaced.
After the last two injectors were replaced and a fresh oil change at 6,000 miles for about three days and 500 miles the engine ran smooth and quiet on start-up or when at operating temp. Engine clatter or “ping” was practically unnoticeable at any speed. A pronounced knock on one cylinder that started after the possible hydro-lock event when the vehicle had 500miles has remained despite the injector replacements and is noticeable most of the time but I suspect is due to engine damage caused by a badly leaking injector and not the current failing injector.
From what I have observed, when all injectors are operating perfectly there is little or no clatter, or knock and little or no smoke on startup, or when under load, but when one or more start to fail clatter, becomes knocking and associated smoking, idle becomes rough, power is reduced and fuel burn goes up. .
My suggestion is that if you notice any of the symptoms I note, or you suspect an injector problem with your vehicle that you insist on having it properly tested by a technician that knows how what to look and listen for, and how to troubleshoot the new common rail fuel injection problems. The technician needs to understand that the Engine PCM does not seem to be able to detect a leaking injector…
An “Engine power balance test” seems to be pretty effective in finding erratic, plugged or leaking injectors, but the tech needs to know what to look for, if the tech is not experience and/or does not understand the test and just performs it as the manual recommends, he likely will miss a bad injector. After my first injector failed completely the PCM showed no misfire or electrical fault codes, and the second dealer missed it on the Power Balance test.
From new, My engine obviously had a problem as it started knocking severely and missing on one cylinder, but after the first injector failed only a Cylinder Power Balance test showed one failed injector. The power balance test also reveled three more injectors were producing more then a normall %100 power but erritacally between 107% to 118%. Shutting off the leaking injectors during the Power balance test also stopped or greatly reduced the idle knock. Turning off normal cylinders produced little or no change in noise.
Both the tech and myself guessed that the only way those other cylinders could be delivering more power then normal was for more fuel then normal being delivered by (leaking) fuel injectors. STAR however would not replace the injectors as it seems they only replace injectors that are making less then 90% power or failed completely Oddly enough the injectors that were producing more then 100% power were also the ones that later failed or leaked severely.
11-17-2004, 03:45 PM
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yes, very good post. i decided to head down to my local dodge dealer this afternoon since things were slow. there was a diesel mech who was standing out front and offered to go with me for a ride and listen to the pinging. he didn't hear anything abnormal and offered to let me drive a new truck to compare which i passed on. i did explain how this truck (2004.5) did not make this clattering sound when it was new. that didn't faze him. i told him that my 2003 SO doesn't make this sound. he said the injectors are not electonic, i thought they were. he said the biggest problems with the 600's has been the injectors and when they go you will know it. rough running and a warning light lit on the dash. wasted trip. nothing better to do though. (he did make reference to the fuel rail changes for the 600 causing a change in the sounds you hear)
i guess i'll just keep the radio blasting.
i guess i'll just keep the radio blasting.
11-17-2004, 04:40 PM
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My point exactly
Might be interesting to ask the “Diesel Mechanic” who says the injectors are not electronic explain why there are electric wires going to each injector, why are those wires are connected to an Engine Control Module, and why it is when you pull the electronic plug to the injectors they cease to function?
Sort of echoes my experience with most Dodge Dealers when I asked them what was making the loud clunking sound and why the engine does not produce much power on one cylinder, and I think well illustrates my point..
From what I have observed, The Check engine light will only come on if there is an electrical fault (I.E. open or shorted circuit, or bad coil in the injector), or if the injector for some reason does not deliver fuel causing a complete and prolonged misfire. It does not seem that the PCM has any way to tell when a fuel injector is weak, partially misfiring, erratic or leaking, therefore delivering too much fuel and thus causing the engine to knock and smoke excessively.
In the final stages of failure my injectors seemed to cause a slight or very rough engine, and I would guess if they stop delivering fuel might cause a misfire warning and engine light, but from what I have seen the symptoms of a failing injector can appear long defore it's noticable, and that the sypmtoms can be different with a leaking injector vs a plugged or electrically dead injector.
I have some video of smoke at startup and sound recordings of my vehicle before and after the failed injectors, and replacement of the leaking ones, and time permitting may be able to put them on the web for review.
Sort of echoes my experience with most Dodge Dealers when I asked them what was making the loud clunking sound and why the engine does not produce much power on one cylinder, and I think well illustrates my point..
From what I have observed, The Check engine light will only come on if there is an electrical fault (I.E. open or shorted circuit, or bad coil in the injector), or if the injector for some reason does not deliver fuel causing a complete and prolonged misfire. It does not seem that the PCM has any way to tell when a fuel injector is weak, partially misfiring, erratic or leaking, therefore delivering too much fuel and thus causing the engine to knock and smoke excessively.
In the final stages of failure my injectors seemed to cause a slight or very rough engine, and I would guess if they stop delivering fuel might cause a misfire warning and engine light, but from what I have seen the symptoms of a failing injector can appear long defore it's noticable, and that the sypmtoms can be different with a leaking injector vs a plugged or electrically dead injector.
I have some video of smoke at startup and sound recordings of my vehicle before and after the failed injectors, and replacement of the leaking ones, and time permitting may be able to put them on the web for review.
11-17-2004, 06:43 PM
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I had the power balance test done and the tech said it did not show any bad injectors. I was sitting in the passanger seat when he did it and several of the injectors where above 100%. I thought that was odd. Why and how could it be operating over 100% efficant? The tech took the truck for a day to try and figure out where the nois was comming from and he concluded that it was the #1 injector but Star wouldent let him replace it because there was not enough of a noticable power loss. The clatter has turned into more of a knock sence my last visit. I never used to be able to hear the clatter cruising down the road with the radio off but now I can hear it clearly. When driving by builings and stuff sound reflects off of it sounds so horible I am almost emabarest to be driving it. The best way I can describe the sound is an older GM car with a 3.1 that had cold score. It is not quite that loud but close. I would like to take it back in but am afraid they will just say the same thing and start ignoring me because they thingk I complaine to much. I would like to get my hands on Brian at Star and politely explain to him that a brand new $40000 truck should not sound as if it is on its last leg.
explain to him that a brand new $40000 truck should not sound as if it is on its last leg.
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11-18-2004, 12:13 AM
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Originally posted by mpd
i told him that my 2003 SO doesn't make this sound. he said the injectors are not electonic, i thought they were.
i told him that my 2003 SO doesn't make this sound. he said the injectors are not electonic, i thought they were.
11-19-2004, 06:51 PM
#9
Interesting post. You mentioned to find a good tech and that they should test for an injector that is leaking down. How does this much leakdown occur to cause this "hydraulic lock" you descirbed and how do you test for it? Short of removing all the injectors and having them bench tested I can't think of any way to test for any leakage with the injectors at rest. Dealers are not supplied with any test fixture to do this. When the key is off the psi does not remain in the fuel rail like a gas engine. It is also true that at this time techs cannot just throw parts at your CTD. You have to jump the hurdles and give them the data from what tests are available and they decide what to send you. This turns it into a long aggrivating process most of the time, but thats the way it goes. Not a whole lot you or me can do about it. On the noise while driving I've also run into some trucks that will change note with different fuels. I also find that the common rail quietness has probably uncovered alot of noises that were probably there all the time, you just couldn't hear it with one violent fuel event. Also someone noted that #1 was noisy. I challenge all of you to listen to each fuel injector line (screwdriver to ear/ stethoscope) and you will all find that number one is the loudest by far. I've already been down that road.
11-20-2004, 11:05 AM
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I can feel the knock in the fuel line from the rail to the injector. #1 has it and othe others are smooth. What I would like to know is, why are so many #1 injectors having this knock problem? 
11-20-2004, 10:25 PM
#12
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I read on here a while back that all the injectors BUT #1 have a dampner of some sort atatched to the fuel line under the valve cover. I dont know if that is correct but I remember reading it on here a while ago. I thought of that when the Tech said it sounds as if its #1 but I dident say anything because they where not going to fix it anyhow. I put a 150 miles on it tonight and it is definatly getting louder than ever before. I am getting sick of it. If Dodge dont step up to the plate and take care of there customers, there is going to be a Duramax in my garage at some point. Those are some silky smooth engines. Plus my wife will be able to drive it again and I wont have to be afraid of the auto tranie.
11-21-2004, 04:53 PM
#13
No dampners on any of the lines. They all go from the fuel log to the transfer tube. It just has to do with the design of the fuel log and line and how the fuel moves in the line when the injector cycles according to tech. With that much psi sitting in a line and being pulsed there is bound to be noise. Why do you think it's a "problem"? Because I pointed it out? They ALL do it. No big thing.
11-21-2004, 07:05 PM
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Unless you have some experience and a trained ear you likely will not know your vehicle has an injector problem, and you can’t count on a Dodge service department to know either. MOST SERVICE DEPARTMENTS SEEM TO HAVE LITTLE EXPERENCE AND UNDERSTANDING OF HOW TO DIAGNOISE OR REPAIR THESE FUEL INJECTION SYSTEMS, OR WHAT A NORMAL OR ABNORMAL ENGINE RUNS OR SOUNDS LIKE, OR EVEN HOW TO TEST FOR A DEFECTIVE INJECTOR OR FUEL PUMP..
to reply to that
I work at a dodge dealership and i acutally am proud that I do know these systems and do know when there is a probelm, how many dealerships you been to, how do you know MOST of them are like that, around my training are there is 4 dealership all with COLLEGE TRAINED/CRYSLHER TRAINED cummins mechanics, and they know by heart the diesel eng, and even know the new diesel better than the older ones, just my to cents worth to tell ya THIS DEALERSHIP knows whats its doing
to reply to that
I work at a dodge dealership and i acutally am proud that I do know these systems and do know when there is a probelm, how many dealerships you been to, how do you know MOST of them are like that, around my training are there is 4 dealership all with COLLEGE TRAINED/CRYSLHER TRAINED cummins mechanics, and they know by heart the diesel eng, and even know the new diesel better than the older ones, just my to cents worth to tell ya THIS DEALERSHIP knows whats its doing
11-21-2004, 09:26 PM
#15
Originally posted by bkrukow
there is going to be a Duramax in my garage at some point. Those are some silky smooth engines. Plus my wife will be able to drive it again and I wont have to be afraid of the auto tranie.
there is going to be a Duramax in my garage at some point. Those are some silky smooth engines. Plus my wife will be able to drive it again and I wont have to be afraid of the auto tranie.