Transmission will not shift to first or second gears?

1994 CHEVROLET SUBURBAN
166,085 MILES • 5.7L • V8 • 4WD • AUTOMATIC
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KIM ROSE2
  • MEMBER
  • 2 POSTS
Lose / struggle power when turning left and won’t shift to 1st or 2nd by itself I can put it in 1st or 2nd manually but yeah, I’m lost. help please.
Jan 29, 2024 at 2:19 PM
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STRAILER
  • ✓Experienced Mechanic
  • 55,238 POSTS
We need to run the codes first, but it sounds like the VSS sensor needs to be replaced.

Here is the location of the sensor and a guide to help you check the codes:

https://www.2carpros.com/articles/buick-cadillac-chevy-gmc-oldsmobile-pontiac-gm-1983-1995-obd1-code-definitions-and-retrieval-method

Check out the images (below). Please let us know what happens.

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Jan 30, 2024 at 2:28 AM
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KIM ROSE2
  • MEMBER
  • 2 POSTS
Alright I’ll give that a go and see. I’ll let you know.
Jan 31, 2024 at 11:20 PM
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STRAILER
  • ✓Experienced Mechanic
  • 55,238 POSTS
We had this problem in the shop not too long back, the speedometer works because there are two VSS sensors in the 4WD models. The sensor that runs the speedometer is in the transfer case.
Feb 1, 2024 at 3:36 AM
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