2000 Camry V6 check engine error code P0402

Had it for months but car runs find. Went to a mechanic and he said it was
the gas cap that wasn't screwed on tight and charged the wife $150 but the
check engine light came back a few weeks afterward. I finally purchase a
OBD2 reader and found the P0402 message. How do I fix this myself? Is it the
same problem components as P0401?

Had it for months but car runs find. Went to a mechanic and he said it was the gas cap that wasn't screwed on tight and charged the wife $150 but the check engine light came back a few weeks afterward. I finally purchase a
OBD2 reader and found the P0402 message. How do I fix this myself? Is it the
same problem components as P0401?

P0402 Exhaust Gas Recirculation Excessive Flow Detected is the opposite problem from P0401, which is Exhaust Gas Recirculation Insufficient Flow Detected but they both relate to the EGR valve.

You can try removing the EGR valve and tube and see if there is a lot of
carbon buildup inside that is preventing the valve from closing. You
may be able to dig out some of the carbon and get it working again.

Another possibility is that the vacuum control system for the EGR valve
is not working properly, and yet another possibility is that the there
is a problem with the EGR valve position sensor. If cleaning out the
valve doesn't work, you can access the factory manuals at
techinfo.toyota.com for $10/day to do the diagnosis.

This seems to be a common code! We see it all the time.

I removed and replaced the vacuum hoses on my '95 Tercel and the code
went away...after 2 years!