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Discussion Starter #1 (Edited)
My friends SS while he was driving just stop accelerating. He let it glide to the curb. There we went and tried all gears and reverse and it's not moving. Tranny fluid is flawless and does not smell burned at all. We put this scanner on it and this is the code that came up was p0160 o2 sensor circut No activity detected bank 2 sensor 2, along with p0174 system to lean bank 2. Again, Transmission fluid is flawless and no burn smell at all. Car is struggling to move now while in drive (hard accelerations is moving it (Barely)
 

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Good for you for scanning it. It sounds like a hard part failed inside the transmission. If the trans loses electrical power, it'll default to 3rd gear in all forward gears, with manual 2nd and reverse available as well. If you've lost those, then you have a mechanical failure or all the fluid leaked out. How many miles on it?
 

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Discussion Starter #3 (Edited)
Good for you for scanning it. It sounds like a hard part failed inside the transmission. If the trans loses electrical power, it'll default to 3rd gear in all forward gears, with manual 2nd and reverse available as well. If you've lost those, then you have a mechanical failure or all the fluid leaked out. How many miles on it?
Not sure how many miles. I'll check tomorrow.

Why no transmission fault codes?
 

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Check fluid level with the engine off for a minute, then start it, wait a minute and check fluid level again. If it hasn't dropped, you've got a pump problem.
 

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I'm concerned as to why there aren't any codes on the scanner.
1996 was the first year of OBDII. It was not complicated that year. GM got a waver and did not meet minimum standards for OBDII. People expect that codes will tell them what part to replace. This does not happen on a 2021 and the information a 1996 OBDII code provides can be vague or misleading.

Should it have a code for what you are describing, maybe but it does not so the factory manual will suggest pressure gauges and other mechanical checks just like older transmissions. The factory service manual transmission section is large and part of it is pages of "if it does this check that"

If you unplug the transmission it should set codes, but this will not help you.

A good transmission shop should give you a fair idea of pump or converter problems in under a hour.
 

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Best tool for verifying transmission trouble.

ATD 5550 Automatic Transmission and Engine Oil Pressure Gauge Kit | eBay

I had an issue where the pressure was pretty much stuck at 180psi. Never really went up, never really came down. Never threw any codes either. I also had one where I mis-installed spool in the valve body and it didn't throw any codes either despite the 2-4 band basically being always on.

PCM can only tell if the 5 valves and the 1 sensor are still connected and not shorted out. It can't actually tell if they're moving or not.

-Brian
 
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For the trans, there are about 6 solenoids in the valve body that control shifts and torque converter. Reason there is no code is more than likely that the PCM see's that the solenoid is working. There is a bare minimum of electronics in the trans compared to the engine. If no codes are set, then you are having a parts failure or a leak somewhere. By the way, those solenoids only turn on and off so you really don't get much for codes. Now, as for dying in flight, it could be the pump or could be the torque converter broke. Either way, that trans needs to come out and get stripped down to check everything out and make sure everything is still good and be cleaned up because you don't need metal going through the trans and take the trans out. A good trans shop can check the trans out
 

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i love how people think if there is no error code or CEL that everything is "ok". do you really need a code to tell you that your transmission **** itself or is the fact that it doesn't move in any gear you select not enough reason?
 
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