SECOND EDIT: Thankyou for all your help, after 4 hours of head scratching we found out that the engine is seized and that it has a internal problem that is out of our power to fix for free.

EDIT: Whoops didn't realized I posted this in the general section, sorry about that, this was meant to be posted in the 4th gen section.

Hello everyone I need your help. My class just adopted a Automatic 98 Green Maxima GXE to fix for a fellow staff member at the college and the ONE main thing that is wrong with it is that it will not fire/start.

I pulled codes and got only a 0304 (Knock Sensor)

Then we proceeded to check-
1. Spark plugs themselves
2. Compression
3. Fuel pump
4. Fuel pressure
5. Coilpacks
6. Fuses
7. Oil
8. Battery
9. Air filter
10. Vacuum lines
11. Check for fuel in the tank

And EVERYTHING was good. So as of now the car only cranks but it won't fire. Also it makes a horrible grinding sound after cranking for a set time, which we pinned down to missing teeth on the flex plate. But in the time that it cranks to the point where it makes the sound, there should be enough time for any car to fire.

On a side note the car is a student project and so we are kind of inexperienced with this kind of stuff and so if you think that we should double check compression or whatever, then I will do it again tomorrow.

And so I come to you guys today to ask for your opinion on what else to check for and if there is a fix you guys have in mind. Thanks!

 

And also I didn't search, sorry!! Searching right now...

 

starter maybe? or even alternator

 

Most likely one of the crank sensors. There are two on the car, POS (position) is under the car on the bell housing, it looks at the flywheel. REF (referance) looks at the crank pully and can be seen by pulling back the splash shield in the RF wheel well.
Check the signals from both of those sensors. They will both cause a no start condition.

 

But wouldn't it throw a code if any of those were out? But I will check those with a multimeter today as soon as I get to class, thanks!

Also the owner of the car is planning to throw away the car to a junk yard, and its outside is in great condition, its just the owner let the car loose. So we have to save it or its going to be another 4th gen Maxima gone from the earth.

 

Part it out in the For Sale forums here. You can make a few $$$ on it.