1997 Toyota Corolla Check Engine Light Code

Hi there,

My check engine light came on, so I took it to Auto Discount to get it decoded. I got 3 errors. Two of them were the same:

1 x P0133 - O2 Sensor Ckt Slow Bank 1 Sensor 1

2 x P0401 - EGR Flow Insufficient

It was suggested to me that I can just replace the oxygen sensor myself. However, I do not know where to find it in my car.

Any help?

Thanks!