2005 altima, check engine light came on....mechanic said it was the crank shaft sensor...replace both of them......light comes back on a week later, then goes out, then comes back on....seems like whenever I fill my tank the light goes off and when I get to about 1/4 tank it comes back on

SOURCE: crank shaft sensor

o.k... on the very botton of the engine... right above the harmonic balancer... better known as the crankshaft pully... it shold be just off to the side a little

SOURCE: CRANK SHAFT POSITION SENSOR 20002 NISSAN ALTIMA

1st, Nissan had a recall on Crank position sensors for 2002-2006 Altima's. Check with you dealer before you go doing any repairs. You may discover you can get your car repaired at no charge.
NHTSA Campaign ID number :O7V527000
Symptom: Erratic behavior. Stalling and no starts and very difficult to diagnose due to the time frame in which the component actually malfunctions. The warranty should not be limited to the original owner.
I would also need more specifics as to which engine you have so I might assist you in where the location of the sensor is. The Altima had a 4 and a 6 cyl engine offered that year.

SOURCE: where is the crank shaft sensor located on the

The crankshaft position sensor is on the right rear of cylinder block, below starter motor.

Testimonial: "great just what i asked realy helpful thanks"

SOURCE: my 2005 altima has trouble starting. it cranks up

most likely the starter needs replacing.....but check its wiring for cleanliness and proper tightening...not sure if the starter show up on the diagnosis device.....betcha it is the starter...hope this helps...thanks

SOURCE: 1996 nissan altima shuts off while driving.

ok the nissan altima has the same engine as any nissan 240sx from 92+

its a ka24de engine 2.4liter dual over head cam so if they cant find anything under the altima tell em to check a nissan 240sx of the same year.

as far as the car dieing it could be a few things idle air control valve clogged pcv valve wich is stupid hard to replace i have a 95 altima your almost better off pulling out the entire engine. and other things sorry. I cant assist with your main problem but thought id drop some advice.