Help with a Noise!

[DDoctorian]

I got in my 04 3500 to come home tonight and notice the Cummins had developed a slight miss and a distinct tapping sound. The tapping got faster as the rpms increase. Injector? Valve? EdgeAttitude? I weighed about 28000 and could noticed a loss of power at the begining of the drive home. After about 10 minutes on the road everything seems normal and by the time I was home I couldn't detect any miss or tap. Any ideas where to start looking? Thanks for your help.



dd

 

[MMeier]

My vote goes to injector or valve seat, how cold was it? A signature and location can help quite a bit on such matters.

 

[MCummings]

Ours had a tapping noise too. Sounded like a gasser that had a dydraulic lifter collapse... Does yours sound like that?





Merrick

 

[HSpiering]

I wonder if ULSD has any thing to do with it if it is the valves?

 

[DDoctorian]

Thanks for the ideas. The pickup sat saturday night through this morning. Started normal today and ran good all day. No tapping. Go figure. It did sound like a gasser lifter tap... maybe alittle louder. Would a check engine light come on if it were an injector? No matter, I guess we will have to wait and see now. Thanks again for your help.



dd

 

[JEstes]

Since it cleared up, I'm betting it was dirty injectors. The injectors can develop carbon deposits on them from excessive idling or just not driving hard enough. How much pulling had you done before the tap started? Also, do you let it idle for long periods of time? Mine will start a little tap if I don't pull anything with it for a while. I got back from a trip to Atlanta last week, and the truck ran almost perfectly. During the trip the EGT's were consistantly at 900+ and I did sustain 1000+ a few times. You've got to remember, this engine is an industrial design, therefore it's intended to work its butt off.



Personally, I wouldn't worry about it unless the noise appears without any predictability. Just take an oil sample to be on the safe side, and keep on going.