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Sluggish acceleration from a stop

Old Jul 30, 2022 | 10:41 PM
  #11  
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Originally Posted by greg8453
Has it been getting worse over time? If so, the cat is likely getting plugged. A back pressure test may be in order.
No, the behavior has been about the same, before and after the transmission rebuild. I wish I had a GoPro (or at least a head mount for my phone). I would record it.
Old Jul 31, 2022 | 03:34 PM
  #12  
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In the OP, the OP said, “At highway speeds, it will quickly go from 55-75…” but we seem to have forgotten that. I don’t think this is an engine power problem. I don’t know much about how this transmission works, but have we somehow eliminate not going into 1st gear???
Old Jul 31, 2022 | 10:50 PM
  #13  
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Dragging brakes?
Old Aug 1, 2022 | 10:10 AM
  #14  
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Originally Posted by PulpFriction
In the OP, the OP said, “At highway speeds, it will quickly go from 55-75…” but we seem to have forgotten that. I don’t think this is an engine power problem. I don’t know much about how this transmission works, but have we somehow eliminate not going into 1st gear???
Wait. The problem is it goes from 55 to 75 to QUICKLY? What is sluggish all about?
Old Aug 1, 2022 | 12:53 PM
  #15  
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It’s sluggish between 0 and 55? I’m thinking throttle body
Old Aug 1, 2022 | 02:02 PM
  #16  
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Fine in high gears, slow in low gears. How could it be anything but the transmission?
Old Aug 1, 2022 | 03:31 PM
  #17  
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Once again, the behavior has been the same before and after a transmission rebuild. Before the rebuild (detailed in another post) it would jerk at city speeds and almost die if left in gear at a stop light.
Saying it creeps in the original post might have been too much. It will drive ok from take off, if you take it slow (driving down the driveway and onto the county road). It doesn't feel like a car that doesn't have a first gear (and I think the shop would have noticed if it didn't have first gear when they finished it). But if I need to take off from a light, or pull onto the highway to beat a car coming the other direction, or onto an on ramp, I can push the pedal halfway down and there is a delay before the acceleration kicks in.
Thanks.
Old Aug 1, 2022 | 03:48 PM
  #18  
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You need to look at live data and see what's going on. You don't even know for sure that it starts out in first gear. Get a decent scan tool.
Old Aug 1, 2022 | 04:42 PM
  #19  
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Clean the throttle body and the MAF sensor.
use CRC kit


Do not manually move the throttle plate! The plastic gears strip real easy!
Old Aug 1, 2022 | 06:59 PM
  #20  
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Originally Posted by Timewalker
Ok, so I got the transmission on my 2011 LT rebuilt at a local shop and saved a lot of money from the initial quotes from the local mechanic and the dealership. Thanks for all of the feedback and help there.
Yes. Back in February. That thread fizzled after the transmission was rebuilt. I re-read the entire thread. (At the time I doubted that a rebuilt was needed and I still do, but that’s water under the bridge.) Last word from OP on that thread was 3/3/2022 and no decisioned had been mentioned at that point.

The codes that came out in that thread were:
  • P0700 Transmission Control Module (TCM) Requested MIL Illumination
  • P0742 Torque Converter Clutch (TCC) System - Stuck On
  • P0842 Transmission Fluid Pressure (TFP) Sensor Circuit Low Voltage
Originally Posted by Timewalker
From a green light, I can press the gas halfway down and it will creep forward for half a block or so. If I mash the gas there will still be a delay, but it will kick in a little quicker. At highway speeds, it will quickly go from 55-75, but that low speed acceleration is getting annoying, borderline dangerous.
Originally Posted by Timewalker
Once again, the behavior has been the same before and after a transmission rebuild. Before the rebuild (detailed in another post) it would jerk at city speeds and almost die if left in gear at a stop light.
Saying it creeps in the original post might have been too much. It will drive ok from take off, if you take it slow (driving down the driveway and onto the county road). It doesn't feel like a car that doesn't have a first gear (and I think the shop would have noticed if it didn't have first gear when they finished it). But if I need to take off from a light, or pull onto the highway to beat a car coming the other direction, or onto an on ramp, I can push the pedal halfway down and there is a delay before the acceleration kicks in.
Thanks.
Poor engine performance does not explain those codes.

I don’t see how those codes were addressed and I bet they’re still there because nothing has improved and I don’t think rebuilding the transmission would fix it. I don’t know enough about how the transmission controls work but couldn’t those codes be caused by external wiring? If so, it would explain why rebuilding the transmission did nothing.

Nothing wrong with barking up the wrong tree. There might be a squirrel up there, too.

Last edited by PulpFriction; Aug 5, 2022 at 02:59 AM.

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