Caliber SRT4 Running lean, Low boost.

[StreetRonin]

So I’ve noticed my car starting to run differently under boost. I’m currently running the 91 octane tune. When I first installed the car ran fine. Full boost spiking 19-20, then settled to 18psi. A/f showing a good 11-11.3. I had also posted my tune to get the CEL removed for my 2-step. Still good after that as well. Now it won’t get full boost at all. It’ll hit around 16psi, and a/f will be about 12.5-13. I’ve checked for boost and vac leaks and it’s all good. What has me dumbfounded is when removing the tune to factory I’ll get full boost and a/f will be at a good 11-11.3. Any insight would be appreciated, thanks.

Just for the record, only mods are catless dp, straight pipe exhaust, N2MB wot box, and HKS bov. Which I already had before installing the tune.

[mikel]

well, the tune cant change, so, more likely something mechanical, check wastegate operation, etc?