Hi,
It could be a few different things. First, have you checked to make sure there are no engine vacuum leaks? Also, an engine coolant temperature sensor can be causing this as well. It provided info for the power-train control module (PCM) which in turn determines what the air fuel mixture should be. If the sensor's reading is wrong, so is the fuel mixture. Interestingly, there not be a code set because the PCM doesn't realize the signal is wrong.
Here is what I suggest. First confirm there are no engine vacuum leaks. Here is a link showing how that is done:
https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge
If that checks good, I need to know if you have or can get a live data scanner. If you have one, let me know what the short term fuel trims are when it is running rough. Also, check to see what temp signal the engine coolant temp is sending to the PCM.
Let me know what you find or if you have other questions.
Joe
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Wednesday, May 6th, 2020 AT 9:15 PM