I’ve never had this happen to my Z before but I have a 2004 350z enthusiast. I was on my break at work and was just sitting in my car with it on for about 15min w the AC on, and then I rolled the windows down and turned my car off. 10 minutes before my break ended, I turned my car back on to drive it back to my job and I sat with my car idling and I noticed my rpm’s start to drop and all of a sudden it clunked out. I tried to start it and it barely wanted to turn on. I didn’t have time to look at my car so I waited until after work. I started my car just find, popped the hood noticed nothing wrong, then I started to drive home. About 20 minutes down the road it stalled again. I’ve never had this happen before.

I first thought it was my battery connection because it got loose when I hit a bump in the road once. So I reconnected it yesterday and it started perfectly fine and everything sounded good. However I am still concerned that there is something wrong and that it will stall again, so I am going to drive it around the block today to see if it will stall. Some of my friends who are mechanics said that it’s possible my MAF sensor needs to be sprayed clean, my oil sensor needs to be replaced, could be my alternator, could be a fuel pump (which I really don’t think is what I need) or could be my timing belt OR I should just do a oil change (which I am going to do because I’m getting close to that time)

Im still learning mechanics as this is my first dream car and I am slowly Learning as I go but if anyone has any ideas what it might be please let me know

 

first thing is get a scanner on there and check for any codes. This sounds like possible cam or crank sensors. Dont guess around and just scan it before doing anything. Also check your battery connections that there is no corrosion build up and that the posts are tight and not lose.

 

Gotcha! Yes, I'd rather see if it's throwing codes before I take it in or start to buy things I don't need. Thank you! Hopefully this problem gets solved

 

Given the history with the battery connection, it's possible your alternator is failing or has failed. If you have a basic volt meter, check the battery voltage level with the vehicle off, then check again after starting it. A healthy battery should be 12.4-12.8V+ and with the engine running, you should be seeing 13.3V-14V. Normally engine's don't just stall with a bad alternator or battery. You would notice accessories not working correctly or issues with the starter struggling to turn over the engine upon startup, dim headlights, etc.. Running the AC does put a heavy electrical load on the vehicle, so if you have a weak battery with a dying alternator that has the potential to stall out the engine when a major load is introduced causing voltage drop. Were you running the AC both times the engine stalled?

I'm personally leaning towards an electrical sensor issue. Possibly your MAF, but bre240z makes a good point about crank and cam sensors. Generally speaking those issues will throw codes, so best to run a scan before shooting the parts canon. Also, if you can find a way to re-create the issue, that would help pinpoint the cause/source.
Cheers!
-Icer