Basiclly what the title says how do you fix it and would it be better just to replace the motor or fix it

The Pontiac Grand Pri? Or a KA as in a Nissan engine (like the section you posted this in)??

If the rod knock is in the KA then rebuild.

If its in the Grand Pri junk the car or replace the engine.

Good luck!

The KA and how hard is it to rebuild because im kind of a noob as in never really worked on a engine so i dont know

Ok good. What is your budget? Whats it going in and is it a DOHC or single?

If you have never worked on an engine I don't suggest you do it by yourself. Grab an (experienced) friend/dad, some pizza, and a case pull the engine out then take it to your local machine shop and have them rebuild it.

forget the friends and dads if they have not rebuilt a KA. Go to a machine shop, give them aftermarket pistons and rods and tell them that after they get the block cleaned, you want it bored and honed to match the pistons. Tell them then you want the crank polished to fit new main bearings. Tell them you want new frost plugs because hopefully they were smart enough to dip the block with them out. Hopefully they also avoided hot tanking the head... because its aluminium.

Rebuilding is ok, but for just a couple hundred bucks, you can have a stout block.

...if you are experiencing knock, try emptying your gas tank and running a higher octane fuel. Are you sure its knock or valves ticking?

I am sorry if I'm bumping 'old threads'... but doesn't anyone here ever followup afterward?