# Code P2A00



## firstforme (Feb 21, 2018)

First a little history. @006 Sentra S 1.8L. Bought used. Had codes for oxygen sensor upper and lower, evap, mass air flow sensor. After a couple of weeks was hard to start seemed to me it did not maintain fuel pressure. Replaced fuel pump assy and that problem gone. Cleaned evap. Replaced upstream and downstream oxygen sensor. Last but not least replaced Mass Air Flow sensor. Found a new AISIN for $20. Drive car about 30 miles and get P2A00 upstream sensor. From things I had with my Camry that the code is not always the problem it can get a code and be something completely different. I did clear all codes and reset ECU according to what I read on internet. Looked at throttle body, it had a little black carbon that just wiped off. If anyone knows what I need to check I would appreciate any suggestions.


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## firstforme (Feb 21, 2018)

This is what I learned. The oxygen sensor was the wrong one and it is for a 2006 Sentra 1.8L. Looked up my vin and my engine is a QG18DE 1769cc. Got the correct OEM part number and searched for that number. The new sensor will be here in a few days. I did buy a new OEM Nissan sensor for right at $132.00 which is less than the ones at the parts store and the same one Nissan parts sell.


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