I have a 04 LB7. At 2500-2800 every gear the truck surges like fuel is being cut off then on then off really fast.... I have a edge CTS insight and it looks like fuel pressure vs desired is the same.. no codes thrown... ideas? I can get my full 22-23kpsi
Even does it in stock setting. Fuel filter is NEW
I also looked at the pedal position sensor % and when it gets up to the 75-85% range while driving when it starts to act up it drops to around 50-60%. But when I test the pedal sensor while idleing or engine off it goes up and down just fine. So something is telling it to change...WHen in Cruise pedal is 0% and will still jerk and all so it isnt the pedal. I am so lost.. No codes get thrown at all. Could it be any tranny or TC sensors?
I looked at the wires by FICM and alternator, no chaffing.
Tomorrow it is going to be flashed and up dated to the original gm Specs. Hopefully it might throw a code then. We drove it with a scan 2 hooked up to it and it jerked, went slow, struggled, and everything else we talked about. Everything looks ok on the gauges and so on. Also, no codes again. It confused the tech guy. He has never seen this before as well. Also it was at say 2k rpms jerking and slugish, then BOOM 3k rpms. Dont know if it down shifted or Torque converter released if was locked. So... Speed sensor somewhere? (cheap try part, what ya think?)
Even does it in stock setting. Fuel filter is NEW
I also looked at the pedal position sensor % and when it gets up to the 75-85% range while driving when it starts to act up it drops to around 50-60%. But when I test the pedal sensor while idleing or engine off it goes up and down just fine. So something is telling it to change...WHen in Cruise pedal is 0% and will still jerk and all so it isnt the pedal. I am so lost.. No codes get thrown at all. Could it be any tranny or TC sensors?
I looked at the wires by FICM and alternator, no chaffing.
Tomorrow it is going to be flashed and up dated to the original gm Specs. Hopefully it might throw a code then. We drove it with a scan 2 hooked up to it and it jerked, went slow, struggled, and everything else we talked about. Everything looks ok on the gauges and so on. Also, no codes again. It confused the tech guy. He has never seen this before as well. Also it was at say 2k rpms jerking and slugish, then BOOM 3k rpms. Dont know if it down shifted or Torque converter released if was locked. So... Speed sensor somewhere? (cheap try part, what ya think?)