Ok so I did the whole turn the ignition 3 times to read the blinking check engine light. I received codes 37, 51, and 52. So how would I be receiving both 51 and 52. One is a lean fuel mixture and the other is a rich fuel mixture reading from the o2 sensor. Would it be just a bad o2 sensor? There is I believe only 1 sensor on this truck so its the only thing I can think of. Any other suggestions? I don't want to go buying parts and replacing things without full knowledge.