For the past few weeks my truck (2006 LBZ) has been taking longer than normal time to start and has gotten worse in the past two days. Well two days ago under normal driving conditions (no load or anything) I get DTC P0087. Once the engine light was on i couldn't rev up more than 2k rpm (in park or while driving). i cleared the code with my tuner and not two seconds later it was back. at first i was thinking it was my fuel filter since it was about time to change it. Well i changed the fuel filter today and then went for a test run. I first cleared the code before taking off. once i got to not even half throttle the dtc was back. it feels like it's not getting enough fuel and is being restricted. when i got back i turned the truck off and when i started it back up it didn't take as long as it did before i changed the filter. also there is a little bit of black smoke coming out the exhaust when at idle. I have it on stock tune.

Could this be due to those hoses collapsing, bad injectors, bad fuel, or what? Can someone please give me some insight on this.

Performance mods: K&N Cold air intake, MBRP 4" turbo back exhaust, & Bullydog PMT

Thanks,
Clint