PSA: spent $340 on a 'diesel tuner' box off a guy on Facebook and it just tricked the rail pressure sensor
Bought the box in February because the seller swore it added 60hp to his 6.7 and it was plug and play. Six weeks later my truck threw a P0087 and the shop in Amarillo pulled the tune file and showed me all it did was lie to the pressure sensor, and I was down $340 plus a $600 diagnostic and pump inspection. Has anyone actually gotten a real gain from a plug in box, or is this just how all of them work?
What did the shop actually find when they pulled the file? I'm asking because there's a difference between a box that just clips the rail pressure signal and one that also messes with pulse width and timing. If yours was only touching the pressure sensor, then yeah, the ECM never sees real fuel pressure, so it can't pull fuel when it needs to and you get the P0087 plus a pump that's been running dry. Did they say if your injectors got hurt too, or just the pump? That $600 diagnostic might be the cheap part if the CP4 was eating itself the whole time. Curious what codes besides the 87 showed up in the history.