Engine knock

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I have a similiar knock coming from the engine when cold... After it heats up a bit it goes away to a lesser degree but is still there... Additionally, after the transmission shifts into OD at about 40 mph, the engine and truck shutters as if something was not firing... What could be the cause and can anyone help me out??

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Jeff Pilnicki, '94 Dodge Ram 2500, Mostly stock, Chrome Brush guard, modifying exhaust to straight 4" pipe w/5" tip

 

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Hi Jeff,
I'm not sure what it could be. I went through several checks before I figured out where the noise was coming from on mine. I was getting the noise mostly after accelerating which caused the exhaust temperature to climb and then immediately cool when decelerating. The metal expanded enough to cause the sound that I interpreted as a knock. It turned out that my exhaust manifold had been over heated enough times to cause it to shrink which in turn broke the ears on my cylinder head. In your case, however, the knock along with the miss may indicate a injector problem (so I'm told). Good luck and hope this helps. To all you bombers out there - Take A Look At Your Exhaust Manifold! If it is shrinking to the point that it is hard up against the bolts, get a new manifold ASAP!

 

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Thanks for the info Dieselburner... I too suspect an injector and I have done the crack the line gig already with no apparent difference in engine idle... I guess I may have to take out the injectors and have them tested... I am getting 18 MPG with the brush guard on the front... I hope someone else has more insight to my problem... Thanks again!


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Jeff Pilnicki, '94 Dodge Ram 2500, Auto transmission, Mostly stock, Chrome Brush guard, modifying exhaust to straight 4" pipe w/5" tip