So, I've had this problem for around 6 months now and it keeps getting progressively worse. When my radiator fans come on my car will just shut off, or the rpms will flutter in between 200-650 and sometimes it won't die, and sometimes it will. I've replaced the fan motors, new oem maf, new alternator, cleaned the throttle body, new plugs, new ac compressor(thinking the clutch might've started to seize and slowed the belt down when the fans and ac are on), and checked multiple times with different code readers with no luck (no codes, no code history, and no pending codes). Any help would be deeply appreciated. Btw, I have an 05 base package with a VQ35DE and manual trans. I have an intake, and an exhaust. Pretty much stock. I can't think of what it might be, a friend told me I need a tune but I can't fathom a z with only an intake and exhaust needing a tune. Thank you in advance for any help.

 

Bring it to a reputable shop to troubleshoot and diagnose the car, compression test, etc...

Running an intake and exhaust means more airflow which means you are running leaner than normal. A Tune is always necessary to make sure your vehicle is running optimally and safely, running a car lean as !#£& at wide open throttle for a long period of time is just asking for knock and detonation to ruin your motor.

 

This. Bad. Do a search on everything that's gone wrong when people try this on a Z.

 

It didn't mess anything up, I had the problem prior to cleaning the tb. And I see z's all the time with simple intake+exhaust without ever tuning with no issues, I just got a number of a guy that does diagnostics, so I think I'm gonna have him troubleshoot it for me and if he can't find anything ill get it tuned. I just can't believe I need a tune with such little modification.

 

Let us know how the diagnostic goes. Hopefully, it's a simple fix. I highly doubt you need a tune for the mods either. Depending on your mileage though, it might be time for a tune-UP. If you're having load issues, make sure all your grounds get checked.