To clean carbon from valves I pore alot of Deisel in the air intake of my Grand cherokee m-2000 6Cylinder 4L while the engine was hot running. Well it was a mistake. during the process suddenly loud Knocking sound start ed from the engine. If I will remove air rocker rod of Piston#2 the sound disappear.
I have replaced the Valve Lifters, Grind the valves, observed the Pistons from top but still the sound is there.
I am feeling that sound is from cameshaft. Now I am in process of removing came shaft. The jeep is in my garage, so far I can pull the came upto 6-inches, It looks stuck.
For this jeep engine block has to be removed from jeep to replace camshaft bearing or not ???
I want to replace only front bearing
Please advice

 

The sound probably goes away because you are taking the load off of that cylinder. You may have a damaged rod bearing on that cylinder. And I wouldn't advise diesel for anything to do with a gasoline engine.

 

But if I remove the sparking current or connection of fule injector for Piston#2 the Knocking sound will still be there. Also the frequency of knockin is about 6/Second, if it is from Piston connecting rod the frequency should be about 12/Seconds as engine idle rpm is 600-700 corrospond to 12/Sec and the came shaft has half RPM 6/seconds