I apparently am having the same problem. When I put my reader on the car, it indicated a malfunction in the EGR valve. I took the car to my mechanic and he tested the same thing, but his reading showed that it was too lean and it had to do with the Oxygen sensor. The Sensor was 170 dollars and with 1 other item the bill came to 298 dollars. that was a couple of weeks ago and now the Check engine light has returned to full brightness. It is due for an oil change, if you want to write to me in a couple days, I will tell you the outcome. It is a 2000 Toyota Carol la fully loaded.