Engine idles fine until it reaches normal operating temperature, then idles rough and stalls?

Only at idle runs fine if gas is pressed if driven too long like this the screen reads reduced engine power, but no change to RPMs, no change to speed or power. Code read intake air temperature sensor, so I replaced it and the problem was not fixed. Also, cylinder 1 is running lean timing chain was just replaced due to broken guides, VVT solenoids both have been changed. I didn't notice the problem until after I changed the solenoids. I hope you can help.