Let me start by saying this is my first post in these forums and my first 350z. I'm not new to tinkering on cars and doing my own repairs but this one has me stumped. First off, the car is bone stock, no mods done to my knowledge. It's an 05 DE 6-speed and I'm not sure if it's the Grand Touring or the Enthusiast, all I know is it's the convertible with the brembo calipers. About a week ago I was driving home from work when the car felt like it struggled a bit leaving a stop light, then the VDC and slip lights came on. Other than the lurch at the light and the lights being on the car drove home fine, but I noticed that the car would take more cranks before turning over fully the next day. the VDC and slip lights came back on but the car drove fine yet again. While at work I dug through these forums looking for a solution, and I found a lot of people solved their issue with a new crankshaft senor. I stopped at the auto store on my way home and got a new sensor to put in once I got home, but the car wouldn't start in the parking lot. after about a half hour it finally started again, and I drove it home to put the new sensor in. Car still wouldn't start, so I dug out the OBD tool and to my surprise, no codes. I dug around more and found a few posts relatively close to my issue where the car wouldn't start after replacing the sensor. Some had throttle body issues, some had camshaft sensor issues, etc. I've only had the car about 4 months so I decided now would be a good time to do a complete overhaul. So here's where I currently sit: I've replaced the crank senor, both cam sensors, (3 times and the final time I used all OEM from dealership sensors). I've replaced the throttle body with a new one (even got a new intake filter). I've replaced both valve covers and redone all gaskets and old hoses to fix the oil leak. New oil pressure switch, all new spark plugs and coils. Car still will not start. I'm over 1400 bucks into this just in parts trying to figure out why this car won't start. When I had the intake off I noticed the throttle body valve wasn't opening so I held it open and let my girlfriend crank the key so I could watch it to see if it responded and the car actually did start but then the valve kicked shut and the car just died from air starvation. I'm narrowing it all down but I'm just stumped boys. any ideas I haven't tried? Sorry for the long post.

 

Not all diagnostic tools are created equal, I'd be looking to get a complete diagnostic service before shot gunning the problem further.

 

The lurching and taking longer to start with the VDC and SLIP lights would tend to point to failing cam and/or crank sensors. You should always use OEM for those as opposed to aftermarket replacements. It sounds like you did the third time around. There must be something else going on at this point or you possibly caused another problem while you were firing the parts canon at it.

Since you also replaced the spark plugs and coils, make sure you connected everything back correctly and you didn't swap any of the wiring harnesses.