Break you post up into paragraphs please. It makes it easier to sort through.
First. The code 52 is a critical code. If that's present the ECU will DUMP a lot of extra fuel in and pull a lot of timing advance. You need to take care of that FIRST. Do a search on the forum for knock sensor rewire and make sure they're both actually present and connected (there are two sensors on the GTE block, only one on a N/A).
The next codes to look at are the coolant temp and the O2.
The stalling, crap drive-ability and difficult starting cannot be looked into any further until at least the coolant and knock codes are fixed; The knock code is the worst of them all.
__________________
If something breaks or you need to contact a member of the administration please post HERE. Unless it's a private or administration matter please post it on the forum. It benefits no one else if car related questions aren't posted for future users and takes away from the time I'm able to spend helping on the rest of the forum.
If you're so inclined I'm always more than happy to accept tips via PayPal. 
Tip Jar ---> 
|