The knock sensor is on the firewall side of the engine. It's hidden below the intake manifold and above the oil filter.
You will need a 12mm box wench. I just removed mine from the bottom while lying on my back in the driveway. It took some time.
Do NOT take off the fuel injector rail like I did as some web advice says (they were saying you can get it from above between the intake runners = no way.)
I changed my knock sensor because that was the trouble code my car gave repeatedly. Problem (stalling and not starting) was not the sensor.
Now I think it's the EGR that's stuck. It's way easier to replace as it's on the top of the engine on the firewall side. Haven't done the repair yet. Just warning you that it's not always the Knock Sensor despite the trouble code!!!
It is located on the backside of the engine. Go to youtube and type in how to replace camshaft sensor on 2005 Nissan altima and it will show where it is and how to replace it, that is how I did my one.
where is it located
where is 2005 Nissan speed sensor located
The crankshaft sensor on the 1998 NISSAN ALTIMA is located next to the radiator side of the harmonic balancer
where is the knock located on 2001 nissan altima 2.4
I paid $229.00 at a Nissan dealer
Motor
It's a recall, dealer will do it for free.
its located in the trottle body
where is speed sensor on 2000 nissan altima What are the procedures on installing a speed sensor on 2000 nissan altima
It is in the oil pan. Nissan has had a recall to reprogram the sensor. They may have to replace the sensor for free. It cost about $600 for repair.
In a Nissan Altima.