Yesterday I decided to change the brake pads on my car and i did. so while i was at it i decided i'd get rid of my check engine light and replace my o2 sensor. i went to the dealer to buy a knock sensor and an o2 sensor (cuz i was getting both codes). the tech (who knows me) told me that the ecu on a 1997 maxima was not designed to test for a knock sensor malfunction. he said it was a ghost code and that it came out as a result of the o2 sensor. that kinda goes against what ive heard on the org but i didn't wanna insult him so i just bought the o2 sensor thinking if his speculation was full of $hit i'll just come back and buy the knock sensor. so i replace the o2 sensor and damn what a difference. I think it must of been fu*@!n up the engine timing or something but the car felt really different...in a good way. Anyway i drive it really hard for like five minutes park it and when i turn it back on and drive away like 3 hours later there goes the check engine light. AHHHHHHHHHHHHHHH! i screamed like a little Bit@h and my mom thinks i'm going crazy cuz i pull the car to the side of the highway to run and ecu diagnostic. I run the diagnostic and it gives me 0905 i check the ol' haynes manual and it tells me its the crankshaft positions sensor. WTF is that. I searched around the org and found out it's not that bad but WTF is up with all these sensors that go on the 4th gen. I had my previous car for one year and my mom had it for 3years--NEVER A GOD DAMN CHECK ENGINE LIGHT! i drove this car (93 Camry) til 148k miles and NEVER A GOD DAMN CHECK ENGINE LIGHT! This max is fairly new compared to the camry (only 69k miles)don't get me wrong 4th gens are phat and i love them but i've only had the car for 5 months and it's my second check engine light. i don't know if it's a mental thing but when the check engint light is on i feel my car weaker can this be. so i guess today i'll replace or try to clean as i saw in a post mr. crankshaft position sensor and if the light comes back...i don't even know whats gonna happen but lets assume it ain't comin back. and ohh i guess the tech was right and cuz both codes went away