No power and seemed to have cut off 1999 Lexus RX300

Lexus RX300

No power and seemed to have cut off

A few weeks ago my 1999 Lexus RX300 started running rough and using more gas than usual. The check engine light had been on since I bought it in
September but there had been no issues before this. Took it to Advance Auto and had the computer scan done, Cylinder 1 and 6 misfires. Replaced
all coils and spark plugs, reset the light. Ran good for about 3 days then it was hard to start and keep running, figured it was cold natured and began
warming it up for 15 minutes or more before driving. A couple more days later the check engine light flashed a few times, car acted like it had died (no
power and seemed to have cut off), then the car was shaking and acted like it had been shifted down suddenly (transmission revving and RPms racing).
My dad ran a scan on it, but no codes or anything show up. The check engine light only comes on during these episodes, which last only a few
seconds, and seem to happen more when it’s cold (the weather or the car) and when I take my foot off the gas pedal to slow down. What could be
causing this?

My initial guess without looking at it would be the Intake Air Hose is loose. Check for loose hose clamps from the engine air cleaner/filter assembly that connects to the MAF Sensor. Or a loose hose at or around the MAF Sensor. Probably got knocked loose or accidentally left loose when it was worked on.