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Hard shift and uo, po & p code

Debz7

New Member
Joined
Oct 27, 2022
Messages
5
I have a 2008 LTZ who is 192,000 miles young. Not really had too many problems with her except for normal wear and tear until recently. She started showing a suspension service dash lite then began shifting hard from lst-2nd with intermittent erratic speedometer. Hooked up the OBD and there were a number of codes that showed up: p1133, po69e, uo101, uo100, uo073, po700, uo109. Mechanic said it could be due to ground connection on body rail under driver's door could be corroded or gunked up. I disconnected the battery cables, disconnected the ground wire, cleaned connection, reconnected the connection and the battery cables then went for a 10-15 mile ride. About the same except instead of hard shift, harsh shift now. Parked the truck. Next day started up, sitting in the driveway and she started to run kinda ruff. Turned her off and 5 minutes or so later, she wouldn't start. She'd crank or turn over but wouldn't run. Another mechanic looked at the truck later, obd showed same codes that I got. He tried starting, she ran for a short time and quit. Wouldn't run when tried again, hooked up jumper cables and she would start. Beat on the gas tank, she ran for a little then quit. Said I needed a new fuel pump at about $450. I know some of the codes said that communication with ECM, PCM, FPCM, the oxygen sensor code, and the CAN BUS code would they have anything to do with the fuel pump itself? What about the shifting, any codes apply to that? Any and all help is appreciated.
 
Addition to original post.....

Was able to get her started. Had been parked on a slight hill with front facing down didn't have a lot of gas. Once started drove to gas station and then for another 20 minutes. Had cleared the codes before going to gas station, towards the end of the 20 minute drive started shifting hard again with codes returning. Any ideas anyone??
 
Probably won't fix yours but check the main 175 amp fuse on top of the battery if that's where yours is. Two nuts hold it in make sure they're tight. Also, make sure the fuse holder box is clamped down evenly to the support matrix under it.
 
Probably won't fix yours but check the main 175 amp fuse on top of the battery if that's where yours is. Two nuts hold it in make sure they're tight. Also, make sure the fuse holder box is clamped down evenly to the support matrix under it.
Thanks Huxley, could you send a picture of the 175 Amp fuse placement as well as the fuse holder box...is the fuse holder box on the driver's side the one you mention?
 
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