Oxygen sensors are a piece of cake to install and my wife could even change one.
Do the cleaning on the TB first and if that doesn't solve your problem all you'll have left is the O2 sensors since you'll have to check the TPS when you reinstall the TB anyway.
I forgot to mention, you need to get some new gaskets when you do the throttle body cleaning. When I did mine all the gaskets were wasted. I got mine from Napa and they run me like $6.00 for the TB, EGR, and EGR spacer. Good luck.
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