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4L80E trans question

Could maybe be a PCM problem?
Considering it's an almost 30 year old and primitive processor, YES! The odds are very good that is has corrupted lines of code or even internal physical damage (corrosion, vibration fatigue failure, etc) that could be causing the shifting issues. Much like people like @MrMarty51 and myself having occasional bouts of Oldheimer's!
 
You likely have the internal wiring harness leaking into the connector on the side of the transmission. Very common issue with the 4L80E. Crawl underneath and you'll see the electrical connector on the side of the trans. There should be no sign of trans fluid on or inside the connector. Replacement is a DIY job.

If you replace the connector you'll need to drop the pan. So plan on replacing both the shift solenoids (A & B) and also the filter. When that connector leaks into the external end it will cause a host of weird shift issue/s. Also get a can of CRC electrical contact cleaner to clean the external harness end out. Use no dielectric grease at the connector plug on the side of the trans.


 
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There seems to be a lot more crappers, I mean hackers lurking nowadays! my son's pc just got hacked into somehow this week! I have a home network infrastructure built complete with a large media storage server, he got all his gaming and email accounts hacked into plus his pc tried to attack the server several times. we spent yesterday evening trying to recover his accounts and resetting passwords. tonight I just got done wiping his pc clean and doing a fresh install of windows! Not sure how it happened but I think he unknowingly installed a tracking bug on his pc where someone on the outside had under the hood control of it, found all kinds of unknown files and even a user account that wasn't there before. LOL I kept asking him if his girl friend had access to anything of his and might have had a "buddy" from school playing a practical joke.
 
There seems to be a lot more crappers, I mean hackers lurking nowadays! my son's pc just got hacked into somehow this week! I have a home network infrastructure built complete with a large media storage server, he got all his gaming and email accounts hacked into plus his pc tried to attack the server several times. we spent yesterday evening trying to recover his accounts and resetting passwords. tonight I just got done wiping his pc clean and doing a fresh install of windows! Not sure how it happened but I think he unknowingly installed a tracking bug on his pc where someone on the outside had under the hood control of it, found all kinds of unknown files and even a user account that wasn't there before. LOL I kept asking him if his girl friend had access to anything of his and might have had a "buddy" from school playing a practical joke.
Internet porn sites?
 
Internet porn sites?
15 year old hormones. Lol. He was upset at us yesterday after the wife and I stopped for lunch at Hooters over in the next town after a trip to Sam’s and didn’t take him with us. LOL. I told him. “Meh. You wouldn’t have liked it, that town is nuttin but crazy college kids !!!
 
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