Well, I hate to say it, but Ive got an odd knocking coming from the engine. I suspect its injector knock, but havent ruled out exhaust leak or even loose converter bolts. I'll be doing those physical checks on Saturday when I have more time.
a) I can only hear the noise in the cab, not when Im standing next to the truck, or if someone else drives the truck past me.
b) The noise is not as obvious when the engine is cold, but gets louder and more pronounced as the engine gets to operating temp, but I still cannot hear it outside the cab.
c) The noise follows RPM, both up and down, and is more prevalent when the engine is working to get the truck up to speed, not when "cruising" with light foot on accelerator. It is also not as "loud" at idle, compared to higher rpm (2000ish)
d) Noise is continuous, which leads me to believe its coming from all 8 cylinders, not just one or two.
e) Engine is still maintaining ~30psi oil pressure at idle, and pressure rises smoothly with RPM to 60+ and does not fluctuate at steady speed, hoses are NOT hard, and engine still has better power ("jump") than it did before the rebuild, so Im ruling out a bearing or fastener problem. Balance rates on the injectors are all +/-1 or so.
f) I am running the stock tune.
Could it possibly be valve adjustment? I do not have a rough idle, engine does not bog down under load (in fact, it runs damn good at higher RPM---Merchant can attest to that), and I get no "ticking" as when the adjustment would be too loose. I set them all at .012 using the method outlined in Alldata.
I am just wondering if I can somehow do a test to see if it is the injectors knocking? Maybe ramp up rail pressure with the DVT function in EFI to see? Is there a way to check injector flow rate somehow or can pulse tell me anything?
If it IS injector knock, and not something more serious, how do I "tune it out"?
Any help appreciated.
a) I can only hear the noise in the cab, not when Im standing next to the truck, or if someone else drives the truck past me.
b) The noise is not as obvious when the engine is cold, but gets louder and more pronounced as the engine gets to operating temp, but I still cannot hear it outside the cab.
c) The noise follows RPM, both up and down, and is more prevalent when the engine is working to get the truck up to speed, not when "cruising" with light foot on accelerator. It is also not as "loud" at idle, compared to higher rpm (2000ish)
d) Noise is continuous, which leads me to believe its coming from all 8 cylinders, not just one or two.
e) Engine is still maintaining ~30psi oil pressure at idle, and pressure rises smoothly with RPM to 60+ and does not fluctuate at steady speed, hoses are NOT hard, and engine still has better power ("jump") than it did before the rebuild, so Im ruling out a bearing or fastener problem. Balance rates on the injectors are all +/-1 or so.
f) I am running the stock tune.
Could it possibly be valve adjustment? I do not have a rough idle, engine does not bog down under load (in fact, it runs damn good at higher RPM---Merchant can attest to that), and I get no "ticking" as when the adjustment would be too loose. I set them all at .012 using the method outlined in Alldata.
I am just wondering if I can somehow do a test to see if it is the injectors knocking? Maybe ramp up rail pressure with the DVT function in EFI to see? Is there a way to check injector flow rate somehow or can pulse tell me anything?
If it IS injector knock, and not something more serious, how do I "tune it out"?
Any help appreciated.
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