700r4 transmission no forward gears, only reverse?

1990 CHEVROLET ASTRO
130,000 MILES • 4.3L • 6 CYL • 2WD • AUTOMATIC
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ALLYSA STORNELLI
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I just bought the vehicle listed above with the transmission disassembled. I rebuilt it, and put it in the van. It won't go forward in any gear, reverse works fine though. Fluid level is good, TV cable seems fine, although I'm not totally sure. The engine revs when I press the accelerator, but it just won't move... What could it be?
Jun 7, 2023 at 8:58 AM
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STRAILER
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It sounds like the first gear shift solenoid is not working or the gear range sensor is shorted and not telling the PCM it is in gear. Let's run the codes to see what comes up, this guide can help:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

Here is how to change the gear range sensor in case you need it. 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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Jun 7, 2023 at 12:03 PM
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ALLYSA STORNELLI
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I ran the codes, nothing comes up.
Jun 11, 2023 at 4:01 PM
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STRAILER
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I have seen the gear range sensor cause this problem, here is how to change out the gear range sensor. Also did you use the same valve body as the old transmission?
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Jun 12, 2023 at 9:30 AM