2007 350z hard start/idle is low/high, can't run.
 

My car has been having hard starts (on and off, always figured the batter was just old) for a while now. One day heading home from work my car nearly went into a stall. The car began to shake, the slip light came on, the throttle wasn't very responsive. I pulled over and attempted to start the car 10-15 minutes later and nothing. I figured maybe it was the cam shaft sensors, so I replaced the two (driver and passenger) in the rear of the engine towards the firewall (back of the engine nearing the inside of the car). Still no dice. The car has difficulty starting and once it does the idle is up/down. Usually takes a little gas to start it. Once running it seems as if it wants to die and the entire car begins to shake so I kill it before something more serious happens. Any ideas? Apparently autozone said there's 4 sensors. I think I see the other 2 (near the front of the engine), but I don't know how to get them out since when I unbolt the 10mm bolt it seems to be attached internally by wires. Any and all help would be greatly appreciated!

sound like a throttle position sensor. do you have any DTC codes??? or check engine lights?

What's DTC? I've been having a check engine light on ever since I installed intakes/headers/HFC's/y-pipe/exhaust. I've just been ignoring it (I know, bad).

If I could get it to autozone I could get them to put a code reader on it, but I can't. :/

Do you know where the throttle sensor is located on a 2007 (dual throttle body) Z?

A DTC = Diagnose Trouble Code. you can buy a cheep version of the scan tool from autozone around $40. your throttle position sensor is on the inner side of the throtle body. one side has the actuator motor and the other is the sensor.

I got a cheap scan tool from amazon for $20 and it works just like theirs.

Could you please link me?