This is a very off the wall question and I'm just looking for some ideas. For the past couple years at total random my 95 z just doesn't want to start. It will turn over and over and over. So far it eventually starts. This literally only happens 2 or 3 times a year. I was having a misfire issue but I replaced the opti, wires and plugs and runs great. It did the no start thing even before any misfire. Once running, it runs, drives, idles completely fine. Had the fuel pressure checked and that was fine. Funny thing is, first time I drove it after getting the new opti in, after getting it home from the shop, it acted like this. Started at the shop multiple times and again, ran just fine. Next day it acted like it wouldn't start. It's been a few weeks and hasn't done it since. Like I said it only does it a couple times a year. Just looking for some possible ideas.

Edit: Sorry guys, I probably should have put this in the lt1/lt4 drivetrain section :/

 

have you replaced the opti wire harness. goes from opti to wire harness plug on the passenger side of the intake. failing ignition coil/control module can do this. failing ignition switch can do it. is it losing spark or fuel? or both? need to test when it wont start.

 

I don't really have a way to test it when it doesn't start :/ I guess that's about the only way to know though lol. I think I had the harness replaced the first time a few years ago but not this most recent time.

 

pick up a spark checker and a can of starting fluid. squirt some starting fluid in the throttle body and if it runs or trys to then dies there is a fuel problem. if you dont have access to a spark checker use an old, or new spark plug, unhook a plug wire and plug to spark plug and ground the metal of the plug to the engine. then turn engine over and see if it sparks.

 

try to turn the key 3 times without engageing the starter ,could be the fuel pump check valve going ,but they ussaly go all at once .or mine did,gas filter mabey

 

when it does that, and you keep cranking, does it eventually start? I can't really tell by your explanation.

If that is the case, then perhaps try this as your process. Every time you start your car, instead of turning the key to start, leave it in "run" for about 2 seconds, then crank it. See if the random problem shows up in whatever time cycle it has been appearing.

I've seen some Nissans (especially) as well as other vehicles that from time to time, take excessive cranking time to start, and it's random. It might be when the engine is hot or partially cool, but never when completely cold.

If you do the 2 second in run process, it goes away

 

Yes it eventually starts after about 20-25 sec of cranking. That doesn't sound like much but count it out and it's quite a while lol. Also I almost always turn the key on for a few seconds before cranking it. I used to think it was after the car sat for a while (more than a week) but last time it did it, I had just driven it the day before not quite 24 hours even. Anyways thanks for the tips guys.

 

I think it may be the El Nino Effect on the Right Coast.
I sympathize with you 95Z.
As for my '02 SS, various actions happen when starting cold, as in overnight sitting.
Historically, insert key and engine running within 2 seconds, if this long.
This summer, cold starting, crank over 3 different times, then starts on the fourth try - kind of embarrassing.
SECURITY light does go out while cranking, but no start.
Swapped out fuel pump relay and to no avail.
Now recently, turn key to IGN for 3 seconds, then cranks right up, so far in the last 5 starts.
I have been trying to listen the fuel pump running for 2-3 seconds, but bell is sounding and drowns out the 'hum'.