Well, this is kinda difficult to explain but I'll try my best.

For a long time I've had the feeling that something is wrong with my 2004 Z.
Sometimes it just plain out lacks in performance! And it doesnt have anything to do with humidity or temp. since it can vary greatly within the same day without any weather changes.

It's really getting on my nerves since I dont have a clue on what it can be?
Sometimes when i get on the gas, it accelerates very good, other times it's just like pulling a weak rubberband and the car feels like it lost 80 HP or something..!
I really have no idea what it can be, but I would like to have it figured out soon since my warranty is about to expire!
The car is totally stock with about 20K miles on it. When I bought the car it had 10K on it and it didnt act like this at all.. I have been on it pretty hard, pushing it through out the gears pretty often!

Does anyone have any suggestion on what can be wrong with my baby?
cracked piston/ring?
clutch?
electronics error?

Let me know what you think guys.
Thank you.

 

Could be idle sensor , what it sounds like to me. Take to to auto zone let them hook it up to the computer to check the codes,even if you dont have any light on yet that just means it hasnt gotten bad as it will soon then the lights will be on , Auto zone should be able to tell you for free.

 

I've had it on the dyno and it does lack a little performance, but obviously not as much as I thought.. I'm not sure if it's because it doesn't act like on the road or what's going on, but I think it performs very weak on the street.
The dyno shows crank hp and torque, since thats the only way we dyno cars here in Denmark. The temp. and humidity has been corrected so it shouldn't be a factor.