Hey friends, I have a 2008 G37 Coupe with a manual transmission that I got an Uprev tune on a few months ago and I've been having an issue where whenever I'm in first gear at a low speed and give it more than around 70% throttle the car seems to cut power, rev up slowly, then jump and accelerate normally once it hits 15mph. I remember my tuner telling me he made it so that the car could 2 step while rolling under 15mph (don't know why this would ever be useful), so I figured the car probably thinks I'm trying to 2 step despite the clutch not being pressed. I tried contacting my tuner, but he just got defensive and told me its an issue with my car and not the tune.

Other than that, the only other issues with my car are a CEL for an o2 sensor, and a TPMS light because I was too cheap to put sensors in my aftermarket wheels, could these be related? I know my clutch sensor is fine because the car still only turns on when the clutch is pressed. I know this is an unusual issue, so any help is appreciated!

 

Did your tuner add alternate maps?

If not, don't let him off the hook.

 

Would you suggest that the tune is the issue? And no he didn't think it was necessary because I'm running pump gas and am NA

 

I might have multiple tunes if I didn't always want the 2-step. If the tune uses your throttle technique to trigger 2-step, then it's not the tune per se. You might have to specify more than one tune option. Often, the cruise control switches are used to manage which tune you use at any given time.

 

To my knowledge, Uprev’s 2 step should only be actuated when the clutch is pressed. I suppose if my tuner added a map without 2 step that would solve my issue, but he didn’t. Does your tune give you the same issue when you’re on your 2 step map?

 

I have no tune, just regurgitating what I've read over the years.

 

Flash it back to stock and see if it still does it. Easy way to determine if it’s the tune or something else.

 

Would I lose my tune once I flash it to stock? Or does the Uprev tuning suite allow me to download my current tune so I don't lose it (Not sure if its password protected or not)? Thanks for the help

 

The whole point of flashing it back to stock is to get rid of the tune to determine if the tune is causing the issue. Your turner should’ve already tried that with you.

 

I get that, but in the case that it isn't my tune causing the issue (although it likely is), I don't wanna lose it. Plus my tuner isn't being very helpful and he's the only tuner I know of anywhere near me

 

I can help you remotely if needed. Just send me a PM.

 

Update: I got in contact with bythabay, or Eugene from Enthusiast Auto Care. Big shoutout to him, he sent me an ECU with a stock tune to swap out with mine and determine whether its an issue with the tune, or with my car. I swapped it in, and the car ran perfect. Gonna take my car to the tuner and figure out what was wrong with the tune.