Welcome to 2CarPros.
The definitions of the codes are as follow:
P0019 - Camshaft / exhaust camshaft bank 2 correlation error
P0171 and P0175 both are related to a lean condition which means the engine is getting too much air and not enough fuel.
Now, I'm concerned that timing may have jumped on the exhaust cam. Take a look through this link and see if what you hear seems to correlate with anything in the link.
https://www.2carpros.com/articles/engine-noises
Next, most lean fuel conditions are usually related to a vacuum leak. With that in mind, here is a link that explains what can cause a leak and how to check for one.
https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
Let me know about the noise and you may want to check for vacuum leaks.
Let me know what you find. Also, if you could let me know approximately where you hear the knocking sound from on the engine, it would be helpful.
Take care,
Joe
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Tuesday, March 26th, 2019 AT 6:36 PM