2005 LQ4, 170K miles, all stock and all wiring is stock. Recently it starting throwing knock and misfire codes. The main block to firewall ground wire was nearly corroded and gone so I replaced that, still throws these & codes. Also, runs pretty well, hesitates down low once and a while but overall you would almost never know its throwing all these codes.

1. P0327 Knock sensor 1 circuit low input
2. P0332 Knock sensor 2 circuit low input
3. P0325 Ignition coil B primary/secondary malfunction
4. P0300 Random/multiple cylinder misfire
5. Then the code reader show P0327 again
6. PP0332 again
7. P0352 again

Also, not sure why it store the same codes twice like this.

Anyways, any help would be great! Cheers!

 

If you had one really bad ground, you likely have others. Check the ground wires to the back of the cylinder heads.
I think that P0325 is another knock sensor code, not ignition coil.
A common LS1 engine problem is that the knock sensor harness corrodes and needs replacement. You'll have to remove the intake manifold and valley cover for that:
https://ls1tech.com/forums/general-m...r-located.html

Normally when you had misfire codes, it indicates a bad coil(s). But will all these codes, bad grounds and/or harness problems seem likely.

 

There are grounds on the block that are for the coils and injectors. I'd start with those.

Depending on the year, some are on the back of the cylinder head, other years IIRC, are on the bellhousing or the back of the engine.

 

Update?