1998 Avalon rough idle at hot intermittently

I'm having the some trouble with my 1998 Avalon (70k miles).

Runs really rough only hot, intermittently. Starts to happen after a slow down going from high speed to lower speeds. Once it starts it normally keep happening until the car is shut off for 10 - 15 minutes. Sometimes I can take a 200 mile trip with no trouble, then later on it happens randomly on 5 or 30 mile trips. If it happens it always goes away after a 15 minute off period.

I checked a bunch of vacuum lines on top of the motor for leaks, took the egr valve off and cleaned it and replaced a coolant temp sensor.

I've heard people say maybe the MAF sensor can be dirty. Might try cleaning that next.

Thanks for any feedback, you may have.

Old post I know but mscmor, have you fixed it yet?

Old post I know but mscmor, have you fixed it yet?

Have not fixed it yet. I gave my 77 year old dad an ODBII code reader. It only happened once since March this year.
I'm going to have him pull over in a parking lot when the issue happens, keep the car running, and check for codes real time while the issue is happening as a next step. This one has us confused. I'll post something when the info comes through.

Thanks.

The codes should stay in the ECM memory. You don't need to access the codes real time.

Egr valve is sticking