'03 VQ35DE Trouble Codes

[wankerschnitzel]

So I'm happily driving along today, cruising at about 40mph, apx 1,500 RPM with a full tank of fuel and the AC blasting (101F). The motor dies without any warning. Like someone flipped a switch to off. I pop it from drive to N and coast to a shoulder and park. I turn it off for a bit, then try to start. It turns over fine, but just sputters. I wait about 20 min, fires right up. I high tail it home, and it's running sort of off. Missing a bit at low RPM, and knocking a little on acceleration. Take it home, cool it off, starts up and revs tip-top fine for a few, then problems come back upon warming.

No check engine light, however the Haynes states it will not light up unless in it logs an error twice in memory, (other than knock sensors or something)

 

I pull the OBD2 codes with diagnostic mode via blinky engine light technique, 3 times in case I screwed it up (it happens):

 

P0725 = Engine Speed Sensor Input Circuit Malfunction

P0335 = Crankshaft Position Sensor Circuit (blinks this code twice in a row)

P0462 = Fuel Level Sensor Circuit Low Input

 

I borrow El-Cheapo OBD2 'pocket reader'

It says, "3 codes", then lists the above, without having any doubles (?).

 

So I am wondering a few things here.

 

1: So it turns out, this motor has 2 crank position sensors. One in the front down by the oil pan that reads from the crank pulley [REF], and one in the rear down around the bell housing that reads from the fly-wheel [POS]. So, did I get the alarm twice because the OBD doesn't know which one is failing, or might there be another problem to make the ECC(?) think that both are bad? Or just to tell me to change them both (generic code)? Anyone have this experience or similar?

 

2: The engine speed sensor alarm sort makes sense, as it has to do with how the computer talks to the transmission and motor, and when it died it could have been upset that the transmission was turning while the motor was not. Purely speculation, of course.

 

3: The Fuel level sensor alarm? I've never had any fuel delivery problems or gauge problems. Do you think it could be just an arbitrary relationship to the incident today? I mean, the motor died instantly while in motion, maybe there was a moment where it didn't know it was off and threw the code? Or should I do some replacing? (Kind of stretching ye olde budget already)

 

Any ideas and/or troubleshooting advice is very welcome.

[Tungsten]

Knowing Nissan, I would have to say that they are all related to that P0335 code. The crank position sensors go out and the ECU has no idea what the engine speed is. Not even sure why this happens.