Slipping transmission

[andsyd]

I have 1996 Pathy. 2wd automatic about 120k miles. I got it about a month ago. It drove fine all that time except for a late shift into second gear sometimes after the first start of the day. It would rev to 3k rpm before shifting. Would only do it once, rest of the was fine. The other day I was driving and had to accelerate very hard. It seemed to shift through the gears ok, I let off the gas and coasted 100 yards before making a left hand turn. Upon stepping on the accelerator the transmission started slipping badly and finally would not go anywhere. Turning it off and restarting would engage reverse and forward gears and I was able to limp it home. During the limp home it would shift from gear to gear ok for 30 seconds and slip out of gear. So I would shut it off and restart and keep going. Now when I start it up, if I immediately put it in gear (reverse or any forward gear) it engages smoothly and strong with no hesitation. But if I let idle for a minute or two and then shift the transmission, no gears can be engaged without a 10 to 15 second delay. If it idles even longer the delay is longer and sometimes it won't engage at all. Reving the engine has no effect. The only code I have is P0325 (knock sensor) which refuses to erase. Fluid is full and bright pink and still smells like it is in the bottle. I know it is a shot in the dark, but before I bend over at the dealership, I thought I would run it by you guys and see what you think. Thanks in advance

[Towncivilian]

Is the fluid bright pink or bright red? If it's really bright pink, that may indicate water or coolant contamination.