ok so my new to me 97 z28 is hard to start it will carank and crak but wont start unless i turn it over for about 2 seconds then release the ignition switch while leaving it in the run position then hit the starter again and it fire right up could this be my crank sensor or maybe the opti going out i am unfamiliar with the 4th gens this is my first one always had 3rd gens

 

First thing I would do is have the car scanned for any trouble codes.
Slow to start could be any number of things. Fuel pump, temp sensor, etc.
Hopefully you have a code that can narrow it down.

Sort of sounds like your fuel pump to me because when you cycle the key you prime the pump more.

 

try turning the key on and off a few times to prime the fuel system. turn on leave on for 5 seconds, turn off leave for 5 seconds turn on for 5 off for 5. do that three or four times then turn to start. if it starts right up you probly have a fuel pressure problem. fuel filter, fuel pump or fuel pressure regulator would be suspect.

 

Do you hear the fuel pump prim up when you first turn the key on? Start with the simple things:
1. make sure you have spark when its doing this.
2. Check fuel pressure.

I always wait for my pump to stop priming up be for starting my cars, but that's just me i guess.

 

ok i have already scanned and no codes fuel pressure is good not bleeding down and i have tried to prime the fuel system and that didnt help also if you run the car and then shut it down it starts fine within 5 min if more than 5 the problem is back maybe anti theft sys????

 

how old are the plugs? are you smelling gas in the exhaust when it starts hard?

 

The anti theft can be triggered by a wrong key trying to start the car, shuts down the fuel pump. So if you have good pressure then probably not that. Do you have spark when it wont start?

Just pull the front spark plug wire off and have some try to start it as you hold the end near metal. You could also stick a extra spark plug in the plug wire end and seat it where you can see it if by yourself.

 

ill try that then and i dont know how old the tuneup is i just got the car about a week ago

 

I had to do a search to find this, but see if you car is doing the related:

"The PASS-Key II system prevents the engine from starting by controlling the theft deterrent relay assembly and the ECM fuel enable input. If the ECM does not sense the proper pulse width modulate (PWM) signal on the fuel enable input, it will not provide fuel to the engine.

If the wrong resistance value is sensed when the ignition switch is in the "RUN" position, the theft deterrent module assembly will not ground the starter enable circuit and will not output the fuel enable PWM signal for approximately three minutes. This prevents the engine from starting and discourages the thief from trying key codes (resistance values) at random.

If the correct resistance value is sensed when the ignition switch is in the "RUN" position, the theft deterrent module assembly will ground the starter enable circuit and output the fuel enable PWM signal. This will allow the engine to start normally."

pretty much tells how anti theft works on it and pretty much what i just pasted, no fuel.

 

ok but if this were the case my fuel pump would not engage right?? becuase it kick on fine with key on and primes like it suposed to almost seems like no spark (wich as i said befor i will check tomorrow) as it just turns over forever unless i release the started then try again then fires right up