ECU Code 51...and 32

[S3kcboy]

Hey everyone, iv been looking on other threads about the ECU code for 51 but my story is different. I owned a nissan maxima 1995 and have had a couple of misfires so I kind of knew how the misfire would feel on the 300zx i own. Well, i had the ecu pop up 51 previously and the car was struggling. I swapped out fuel injectors and it ran smoothly like a champ. 2 Weeks ago(4-6 months after) the engine was struggling again and the code 51 came on again. I bought a fuel injector, gave it to my mechanic. He took two days ( had other cars to do as well), and dropped it off while i was not home. When i was able to, i turned on the car and it started perfectly, I drove up the block and then the check engine light came up with 51 on the same cylinder ( i checked which was the problem before handing the car). I have no idea what to do, and also a new code popped up, 32 (EGR valve)

Im stumped, I need my car because my State school starts in 2 days

any help guys?

[S3kcboy]

Just went up and down the block, going 60. Car runs perfect but still have the check engine light on

[S3kcboy]

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