I have a 2009 Outlander ES 4cyl AWD. After shutting the car off two days ago the service engine light appeared. After starting it again it was in limp mode. Had it towed to a shop yesterday morning and they scanned it. U0100 and P1590 codes appeared. They reset the codes and took it for four test drives throughout the day and the issue did not happen again. Have driven it a few times since without any issues. The car so far is operating as it should.

Any idea what might cause this? Should I be concerned? Should I wait to see if it happens again?

I have seen a few posts about these codes but no real conclusions.

Thanks in advance!