Thanks for the reply Steve. Yes, certainly would give it a shot and run through troubleshooting. She's on loan and is somewhere out Midwest with a friend so it'll be mid-August before I can re-install and document the problems. I definitely want to try and make it work.Hey Michael,
This is odd and something I haven't heard of before. We ran all of our parts on our JL for several months and did a lot of highway driving and didn't have an issue. Do you know about what RPM you're running at when you feel like you're losing power?
To confirm that it is definitely the intake causing the issue, would you be willing to reinstall our intake and perform the same run? If there's any way you can log commanded vs actual boost, that would be super helpful too (not sure if that's even possible with this ECU right now).
I just went through a similar situation with my GTI (which uses a very similar turbo system as the JL, including the same diverter valve). Sometimes it would feel quick like it should, then sometimes in fourth gear it would fall flat on its face like it had no boost. I thought it was the DV+ I just installed, swapped back to stock DV, issue went away. As soon as I emailed GFB, the issue came back. Turns out my PCV valve was intermittently failing and causing the same symptoms as a bad DV.
All of that is to say that these engines do very strange things sometimes and it's tough to pinpoint issues. This really sounds like a high-load boost issue to me, but either way I'm happy to help any way I can.