I just got Uprev for my Z and the car feels better already. The first e-tune went great but when I sent my logs in for the 2nd e-tune Uprev said I was running rich and the 2nd e-tune should help fix that. I loaded the 2nd e-tune and the car seems to run great but when I turn the car off I get clatter from the motor (just a bit) from the time I turn the key off and the time where the motor stops. Is this a problem? I never had it before I loaded the 2nd e-tune. When I send my next log in I will tell them about the clatter in the email. Is this clatter something that could hurt my motor? Should I just load the first e-tune back and drive it untill I get my next e-tune? This Z is my baby and I dont want to see it hurt Thanks

 

If it happens AFTER you click the key off it's completely unrelated to your tune. The ECU is offline the split second you turn the key off. My guess is it's your clutch/flywheel as G/Z's are notoriously noisy.

 

The ECU remains powered up for a few seconds after you turn the key off. Put your ear close to the throttle body and see if that is what you are hearing - it sweeps open and closed when you turn the car off as a self-test before the ecu shuts down. This is more of a high pitched whine than a clatter, and should not have changed with the etune - maybe you are just noticing now? Can you better describe the noise or get a video?