P0401 code with recently cleaned egr circuit

I recently got a p0401 code (EGR system flow is insufficient) but I cleaned the egr cooler, valve, and pipe as well as the intake manifold less than 10,000 miles ago, I know I got everything very clean. I do burn oil, maybe 1qt every 2,000 miles or so and I have a high mileage prius almost 280,000, but other than that it runs really well. From previous posts it seems like it could be the egr valve went out on me or the map sensor, anyone know how to figure out which of those it could be or what else it could be, I wouldn't think it would be possible for the egr cooler to clog in less than 10,000 miles.

 

Just tried taking the cap off the valve, it moves freely, no stickyness at all.

 

Cleaned the tpm sensor and cleared the codes I'll keep you guys posted if the code comes back or not.

 

I'm not sure what is the correct term for the sensor, but I think we are talking about the same sensor, I have seen people call it the map sensor as well as tpm, but it's the air pressure/flow sensor in the intake near the filter that I'm talking about, I cleaned it with crc mass airflow sensor cleaner and so far I have not had the light come back, but I have only driven about 5-600 miles since then and now I'm on vacation for a few weeks, I'll update after I get some more miles on it

 

I probably am using the wrong term, but it's the intake airflow/pressure sensor that I'm talking about not the tire pressure sensor lol

 

The sensor I cleaned is the one just beyond the filter so I guess that's the mass airflow sensor, if the map sensor is on the intake manifold by the throttle body I would have cleaned that when I cleaned the intake manifold and throttle body, which was about 10,000 miles ago now