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My 2009 5.3 GMT900 flex fuel LMG motor is running rich. Short term fuel trims are on average -12 or lower (don't have an average field on my scanner, but it's at best a -7, at worst a -17, and most often it's a double digit figure). I've tried a new MAP, new MAF, new plugs, new fuel rail sensor, and tested the fuel pump pressure. The pump kicks out about 60 psi on a cold start and holds steady at 43 psi. I have tried resetting data by unplugging the power to the ECM - which works considering long term trims reset. Someone mentioned resetting the TPS. Not sure how with an OBDLink scanner. Other than that, my idle holds at -5 short term trim until long term trims becomes -5, then itll hold closer to 0 short term idle trim. Anything other than an idle has a double digit long term trim in the negatives and anywhere from -7 to -17 short term trim. Alcohol content is at 6.9% which seems right. It runs decent when you reset the trims, then it loses a bunch of power after maybe a quarter mile and goes back to running like a dog at anything besides WOT. Please help I'm running out of options. It recently cut P0172 and P0175 codes on both banks. I installed a short ram Specter intake about a month or 2 ago, but the engine has been running poorly before that. It didn't throw codes before however. All vacuum tubes are secure and I did a brakekleen vacuum spray test and there aren't any leaks I could find.

Hello, I am hoping that you can help me diagnose what is causing a hesitation on my truck when accelerating from a stop. It sometimes also hesitates when shifting at low speeds 10-30mph Truck Specs 2014 silverado 1500 WT 4.3L V6 locking rear end 32,000 miles no codes, using bluedriver scanner red Problem two weeks ago truck took two tries to start never done this before has not happened again last week truck started hesitating on acceleration from stop every time rpms drop from 1500ish to 500ish and then jump back up and truck accelerates I have attached one of the drive logs where you can see the fuel rail pressure drastically change when the engine rpm drops You can see the seven times the truck hesitated at the drops in the graph Started logging other items to see what is happening and found this spike in the temp sensor, attached picture also. intake temp sensor is yellow line and engine rpm is blue line. I highly doubt the temperature actually went from 55F to 135F during my commute. What I have done Checked transmission fluid, truck level and hot. Fluid in the dashed good zone between the holes. No burnt smell. Found the strange temp reading. Truck off Unplugged the mass air flow sensor and drove around large parking lot. Hesitation completely gone truck drive normally for 5 min. Check engine light off. Truck off Plug in mass air flow sensor and drive around parking lot again. Hesitation back Check engine light on with codes for MAF unplugged. Thought MAF was the issue. Bought new MAF and air filter Installed MAF and air filter Problem gone on test drive for 15min, truck fine, no codes. Next day, hesitation is back, no codes Realize I need help. Post on forum. I'm sure I have left out some important information, just let me know and I'll try to answer. I greatly appreciate the help. Thank you.

Sorry if this topic has already been covered a number of times, but, other than the videos on this tool, what is the experience of other members/ I just received one last week and it's awesome! I'm a computer guy and got it all set up, checkered my codes - major body module faults because of the rear tire pressure monitor that the dealer will fix after they installed my new wheels. I'm interested in what other member's experience with this tool as it relates to our trucks.