I think i originally posted this in the new members thread. So im moving it over here in hopes to get any responses.
Hello everyone, I have a 6mt 2003 g35 coupe. Its in great shape recently replaced the clutch and flywheel with an Exedy kit with Chromoly Flywheel. Ive replaced the crank sensor under car as well as replaced passenger cam sensor and will be installing the driver side cam sensor(under intake) tomorrow possibly. Before the job the car had no dash lights on at all. Occasionally the slip and vdc would turn off (lights turned on)while driving but a restart always fixed that immediately. (This was extremely rare with no CEL light to match it with) . Now i am aware that people will tell me to return my intermotor crank sensor and order infinity OEM. My mechanic doesn't seem to consider that to be a real solution and states that my car would not start and run 100% if that crank sensor wasnt getting signal. Now... rewind a bit. My car has a killswitch or mechanics lock whatever you want to call it. its very simple the car will not start without the headlights on. You get in car turn *** push clutch start car. Doesnt really have issues starting. Does not shut off while driving or have those Rev surges or weird stuff going on. I have a nice amount of power and besides that annoying dual mass to single mass clutch chatter i expected to get. It shifts smooth and i have no problems in that area. I was considering returning the second cam sensor and taking new crank sensor out and ordering OEM(since i have no engine light for that p0340 or p0345. Ive cleared the codes and theyve come back. Sometimes it took a few starts or sometimes 10 mins driving. I did ecu reset with gas pedal it came back after 5 mins. Before i took car home from shop because they recommended i drive it a bit and it might sort itself out. They looked for relearn procedures with there scanner. But there scanner is not a consult 2 or 3 device. This is a mom and pop shop with a high end snap on scanner. I did get my hands on it(i work there occasionally) and i looked around and i did not see much regarding any kind of relearn procedures besides throttle and idle relearn. However some people have stated that after new clutch that light and vdc slip and p0335 pesky code has come up and after driving it for a while. It went away and never came back. Today i disconnected positive terminal and i pumped the brakes. Waiting 15 minutes and drove roughly 35 minutes home. The engine light and vdc and slip are off... as of tonight. I recently replaced all suspension and new tires and loads of new parts and am in line for fresh inspection stickers. I need this engine light to go away and stay away so i can drive it the required miles to pass insp and emission. I know this topic has been highly debated. However i feel my mechanic isnt extremely familiar with the nissan infinity family. And has recommeneded i do the other cam sensor as well and i do not feel that is related whatsoever to the crank code but i could be wrong. At the current moment those lights are still off. Will be testing and driving it again tomorrow.If anyone can provide any insight or thoughts as to why my vehicle runs with no issues( hard starts multiple cranks stutters shut offs rev surges and the usual symptoms) Definitely a frustrating issue

P0335 is the code for the crank sensor sending intermittent or consistently wrong data back to the ECM, these cars are notorious for not playing nice with aftermarket sensors. Buy a Hitachi (the OEM supplier) or a Genuine Nissan Parts OEM sensor (same Hitachi but in a pretty Nissan baggy with the price marked up).

Also clean the harness with a plastic-safe electrical contact cleaner to make sure there isn't any oil contamination on the harness. If you still have issues then it's likely damaged wiring between the harness and the ECM, usually it's easier to pull a new wire and splice than try to replace the entire engine harness.

Start with getting the correct sensor, ignore the advice your mechanic has given, he's obviously not well versed with these vehicles and doesn't fully understand WHY an intermittent signal is causing a check engine light on newer vehicles with OBD2 "two failure logic".

How it works basically is the ECM doesn't turn on the check engine light until it receives the same bad signal (or no signal) twice in a row, your ECM receives a constant stream of data from the crank sensor (hall effect sensor, google it) at a rate of hundreds of small signals PER SECOND, it's a wave form of data, if bits and pieces of the wave are missing it can still gather enough data to control engine function but it will send the code P0335 to let you know that enough of the data is missing that THERE IS A PROBLEM. If there is no data at all, complete failure of the sensor, then the car will not even start.

What you have is basically an early warning code that something is wrong, fix it now before it leaves you stranded on the highway.

However, this is 100% unrelated to any VDC/SLIP lights that might be on your dash, separate issue that needs to be troubleshooted. Typically it's issues with either using the wrong tire size or a failure of the steering angle logic.

Thank you for all of that information and taking the time to respond. I am going to start with a hitachi or OEM brand sensor and go from there. When the engine light does pop up the vdc and slip light come on a half second after it. The way i worded it all and it explained was confusing. I also intend to get car in the air and inspect the connection and wires running from it and also the area around it. It ran all the way home fine and the lights came back on when i turned it on. The weird thing ive noticed that is different between my post and the numerous other p0335 issues on these cars is that i dont have any issues starting the car and it has no drivability issues. If it was recieving no signal would the vehicle still start? I am hoping to find some damaged wiring that got further damaged during install and may be causing this issue. When the engine light is off the vdc and slip light go off and they work fine on vehicle.

I replaced all 3 sensors now both cam and i bought a Hitachi crank sensor and installed that to no avail. The p0335 light came right back on. I had the car on a lift and we rotated the fly and inspected all the teeth and everything looks good. As soon as i restarted it and cleared the p0335 code it only took all of 5 minutes for the code and vdc and slip lights to come back on. Going to be tracing wires next and investigating further. Car runs great still.

This is the first time I've ever heard of a P0335 after a flywheel installation where the engine was basically RUNNING NORMALLY. Typically if the flywheel is improperly installed and the alignment dowel didn't match up the engine runs incredibly rough, if the sensor is failing due to oil contamination then there is typically a very long crank needed to start as well as intermittent stalling.

Literally the first time I've heard of it throwing the CKP sensor code but still running normally. It's possible you have a slightly defective flywheel. Ringing out the wires back to the ECM is the next step. See if they have a megohmmeter to verify the integrity of the wire insulation basically it injects voltage into the wire while also checking wire resistance, if there is any arcing it will see the difference in resistance, very common practice in the electrical industry to megger out wires but not so common in the auto industry.

It takes a meter like the Fluke 1587, a specialty digital multimeter that is ALSO a megger.

If the wires meg out and you've had the same issue on two CKP sensors then you have a slightly defective flywheel, if everything runs normally then I would probably have Nissan put it on a Consult-II machine just to scope the sensor and see what signal it was actually sending back and compare to the FSM, ask them for either a screenshot of the Consult result or ask to look at the results yourself while they're testing and take a couple pics with your phone. If the signals LOOK normal then I would ignore the code, which sucks since you have a CEL, but it sounds like you're paying a shop for labor and it's not going to be worth it for a flywheel replacement especially with the turnaround time getting another warranty replacement from Exedy.

However the Consult-II scan might find something else wrong.

Here's what the signal should like like, pic from the FSM.