A "knocking" noise sounds like a bad connecting rod bearing. You may be ready to "sling a rod". These engines are famous for it.
Yes Knocking on people's door and running is Illegal
check to make sure the belt tensioner is functional if not it needs to be replaced
Most of them move some but if your belt is squeeling you probably need to replace the tensioner.
3 MUST haves for an engine running. #1 - Compression #2 - Fuel #3 - Spark check to make sure you have these 3 first.
Running too lean.
Unless you can feel it running rough and knocking - no.
the lifters
This game played by children (and chld like adults) has numerous names all over the world. They certainly include both Knock Down Ginger and Cherry knocking and a hundred more names as well.
Have it replaced.
I just replaced mine because the automatic tensioner pully locked up (which from what I've found online was actually recalled though since I got mine used I was never informed) & melted the pulley & belt. The tensioner was about $90 & belt was about $40. All in all it took about 2hrs to replace both parts & get it up & running again. Good Luck!
Yes, a bad belt or tensioner can be related to a rough idle. If it is not tight enough, or worn it is not able to run as smoothly as needed to keep the engine running smooth.
sounds like you ac compressor is about to crap out.