How hard is this to change? Mine is bad and they want 380 to fix.. Where is this located yadda yadda...



HELP

 

Crankshaft Position Sensor (?) Is that what you mean?

If so, there are actually two:

1) Crankshaft Position Sensor (REF) - it's mounted at the front of the engine, on the aluminum oil pan section below the crankshaft pulley.* Scan Tool Code: P1335 / ECU DTC: 0407

2) Crankshaft Position Sensor (POS) - it's mounted on the aluminum oilpan section at the rear of the engine near the transaxle bellhousing.* Scan Tool Code: P1336 / ECU DTC: 0905

Either is VEEEEEERY E-Z. 10 mins, tops, easily accessible.

You should first run an ECU check yourself, to determine exactly which sensor is throwing the code.

If it is the (POS) sensor that is causing trouble, (before you spend the dough on a new unit), remove the existing sensor from it's mounting seat and clean off the tip, reinstall, reset your ECU, & see if the CPS(POS) DTC is generated again. (This is the one I have experience with).

I got a CPS(POS) DTC once, and did just this: (there were fine metal particles covering the tip of the sensor [which is magnetic]) I assume these particles were confusing the readings generated by the sensor and transmitted to the ECU, which in turn, took the "bad" readings to mean that the sensor had failed & needed to be replaced.

After I did this, I never had the problem again & have had no driveability issues, whatsoever.

*Refer to Hayne's (Section 6-12)

Good luck!



P.S: If you DO need to buy a sensor, check out www.courtesyparts.com, or Tustin Nissan (don't have the url) Mention you're a maxima.org member & get a break on the price.

 

Hello,
I just signed up and cannot post a new thread, so I thought I would reply to this one and hopefully someone will read it. My wife's car has had trouble starting for a while and today it took almost an hour to get it started. I am almost positive it is the CPS, but I don't know where they are located to try and pull them out and wipe them off. I leave town tomorrow and want to try to try this so she won't get stranded or have to get it towed out of our garage.

Could anyone provide me with detailed instructions on how to find these two sensors (from which side of the car, do I need to crawl under it or can they be accessed from above, etc). I work on motorcycles quite a bit but have never done anything to a car other than change the oil.

Thank you for all of your help!

 

CPS is cam position sensor, not crank. In any case, CPS:


CKPS POS (follow the harness down, it's bolted right where the block and the trans meet. Actually the upper oil pan I think, but it's easily viewable):


CKPS REF (it says POS, but that's the FSM for you...):

 

+1 on cleaning them off first.clean all three while your at it, cam and both crank sensors. 10mm gearwrench or ratchet.also on the pos sensor which is the one that reads off the flywheel there is a thin metal piece there too about 1" by 2",the bolt that holds the sensor on goes throught it.you should clean that really good also,preferably with a wire/grinding wheel.check all of them and if still no good buy the needed part from nissan and diy.

 

it can be done in less than a minute. unclipping of sensor and removal of one or two 10mm bolts is all it takes, you dont even have to jack the car or anything. 380 is a rip off its not even worth it to pay someone ten bucks its so easy to do. ask them which sensor (crank or signal plate one) and just buy the sensor and do it yourself.

 

What would you recommend to clean it with?

 

Just cleaned the crank position sensor that is by the oil filter. It was full of oil and dirt. I used some choke cleaner and a good rag. Any degreaser should work. Also wire wheeled the two screws and used a little sand paper rolled up in the little brass rings the screws go into to hold the sensor.

 

Don't over tighten them either. The plastic cracks easily, known from personal experience.

 

The car sat for 10 days. The engine turned over but wouldn't start. Starting fluid got it going for a few seconds so I figured I might have a fuel line / filter / pump problem.
I didn't get a check engine light so I didn't bother doing a readout at first - which I should have done first.
When I cleared the ECU using the VBX method ( http://vbxmaxima.8m.com/ecu.html ) I came up with 0802.

0802 = P0335 and it also calls out the Crankshaft Position Sensor (POS) as mentioned in an earlier post (P1336 / ECU DTC: 0905).
This diagram nicely shows the camshaft and crankshaft sensor locations:
http://www.courtesyparts.com/maxima-...1814_1816.html

23731M Maxima CAMSHAFT POSITION SENSOR
23731T Maxima CRANKSHAFT POSITION SENSOR
23731TA Maxima CRANKSHAFT POSITION SENSOR

I didn't even have to jack the car up to get at 23731TA.
There was enough clearance to remove the bottom cover and see that there was damage to the three wires that go to the sensor.
The red wire was chewed. It turns out that critters like Maximas too!

For reference - The bottom cover is hanging down off the back screw and you can see the passenger-side tires.
The cover screws might snap on you like mine did so be prepared.

I spliced the red wires together for a quick test and it worked. Now it's soldered and taped together good. I just need a good fix for those other broken off cover screws.