i have a gsr motor and when its cold it knocks and after 2 or 3 seconds it goes away and when i rev it at 3 and up rpms it makes the knock, but it doesnt knock at idle,the sound seem to come from the head, i had replace lost motion assemblies, oil pump and adjust valves and the problem still there anyone with experience can tell me what it could be?? the car has not lose any power and it doesnt smoke

 

Rod bearing..

 

can a bad rod bearing cause a low oil pressuere???

 

low oil pressure= increase bearing clearances= motor rebuild time.

 

so i just need to replace rod bearings ??

 

It depends if you did any damage to the rest of the internals? How long has it been knocking? Do you drive it like that?

 

same problem right now good luck

 

100% rod knock.you'll need new bearings.crank.maybe a bent rod in there .depends if you drove it and stuff. just rebuilt the motor.

 

New crank, rods and bearing.