94 Rodeo check trans light flashing..

This has been an ongoing problem but it seems to go away for many months and then come back. I think it has something to do with the hot weather. If I start the truck and don't emmediatly put it in gear the check trans light will flash and there is huge power loss. Also, when I stop the truck and put it in park the trans light will begin to flash. I can restart the engine, quickly put it in gear and it will be fine until I put it in park again. Also, while the light is flashing, I can go thru the gear selector and when going from any forward gear to neutral, I can hear a kind of spinning sound a second or two after selecting neutral.

Any ideas out there? I really can't afford to take it to a tranny shop and I'm a biggie on doing it myself. :iceslolan

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