I recently discovered (the hard way) that my AC pulley was completely destroyed. I don’t currently have the money to fix it so I bought a smaller serpentine belt to override it for now. Every seems to be fine but…
I was driving on the freeway today and my car seemed to stop shifting. I was going 70mph and car was running at 4000rpms. It’s a mild winter here in Michigan but this happened right as I set my heater to defrost for some fog on my windshield. My car auto locks when in driving gears and it unlocks in park; this also stopped working by the time I needed to get out. I checked all of my fuses and my transmission fluid level. All seems good.
When I turned on my car again, everything seemed normal. By this point, I was back to just using my vents for heating. I drive about 30 minutes to the next town over, fog on my windshield again prompts use of the defroster, and I do so when I am close to my destination. Well, wouldn’t you know it… my engine abruptly jumps up to 4000rpms again. When I stop at my destination, the car doesn’t automatically unlock when I go into park.
What is happening?!
Edit: I can confirm that car is downshifting when I go to defrost setting and then overcompensating with the engine.