I cleaned the throttle body recently, but didn't do an idle relearn then. Yesterday I pulled code 0507. I did idle relearn and erased codes and didn't come up after I drove for 10 mins. But this morning I took the car for emissions test and the same code came up again and failed. Any procedure I can follow to solve this for good.

FYI - I recently changed the spark plugs/coils (#1, #3, #5) to solve P0305. After replacing, I got p0300. Then I changed the rear valve cover as well and after that, p0300 was gone.