A customer brought me a 2013 ZL1 with cheap TLF 90lb injectors. Look like decapped Mustang V6 3.7 injectors. Regardless they work well enough but I'm having an issue with lean tip in on cold start. Warm it's fine. It'll stumble significantly for a couple seconds when attempting to rev or take off with 10-20% throttle. This clears up after a 15-45 seconds and the issue can no longer be replicated until it sits for a while. Fuel pressure is fine, car is still on the MAF and nothing is indicating why this should be happening. I assume it's related to an injector parameter. Any guidance as to where I can start to solve this issue?