Vehicle will not accelerate?

1996 JEEP GRAND CHEROKEE
110,000 MILES • 4.0L • 6 CYL • 4WD • AUTOMATIC
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SCXJ
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The engine idles fine and will rev while neutral. When shifted into drive the vehicle will increase speed to about 25 MPH and then won't go much faster. I checked the fuel pressure, and it was about 45 PSI. Replaced both O2 sensors and the output shaft speed sensor. No OBD codes.
Thanks
May 7, 2023 at 7:36 AM
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STRAILER
  • ✓Experienced Mechanic
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This sounds like you have a clogged catalytic converter but to be sure this guide can help us confirm the failure and I have included instructions on how to change the cat out in case you need it.

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

And this may help as well:

https://www.2carpros.com/articles/engine-has-low-power-output

Check out the images (below). Let us know what happens and please upload pictures or videos of the problem so we can see what's going on.
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May 8, 2023 at 4:23 AM
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SCXJ
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Okay, Ken, will do. Thanks for the input.
May 8, 2023 at 11:01 AM
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STRAILER
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  • 55,249 POSTS
Please let us know what you find.
May 10, 2023 at 3:47 AM
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SCXJ
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  • 9 POSTS
Ken,

Sorry I took so long to reply but you were correct, the converter was bad, running fine now. thanks for the advice.
Jun 24, 2023 at 3:21 AM
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STRAILER
  • ✓Experienced Mechanic
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Thanks for letting us know, we are here to help, please use 2CarPros anytime.
Jun 25, 2023 at 4:22 AM
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