Originally Posted by rocketiii

Travis,
I would like to give you a big thank you for this post. By far the best one out there regarding this issue. My car just turned the 100,000 mile mark and prior to that i always wondered if i was going to have the dreaded tranny issues you always hear about. Well last week i noticed my batter light came on. no biggie, seen it happen once before. It went out, and when i got home i check the battery voltage and it was low, like 13v to 13.2, but the light was out. I continued to drive it, well a couple days later the car started shifting weird and when coming out of park the speedo needle would go up to 15 or 20 mph. So, i put the scanner on and of course it gave the 0700 and 0720 code. Bought a new output shaft speed sensor, replaced, was good for a couple miles, then again the problem reappeared. Talked to a tranny guy by the house and we talked about metal on the sensor. There was none on the old one. So, i pulled out the new one to make sure, none on it either. I looked in the hole with a mirror and light, all looked good. So, once i checked all the ground connections and reading your post about the alternator, i went ahead and pulled the alternator from the car and had it tested at Autozone. And low and behold it failed the both the rectifier and stator portions. Replaced with a new one $225.00 with core, and the car now operates perfectly.

Originally Posted by HS3

I have a 2006 Pacifica 3.5 L with 196,000 miles. It has the same issues as the initial post. Revs up on its own while in park with A/C on, shift to drive with brake pedal depressed and it makes a loud clunk and mph needle moves up to 20mph without moving. I initially took it to the local auto part store for scanning, turns out it indicated the ambient air sensor. Guy there had no idea where it was when I asked. Had to Google that. Cost 30.00 dollars and still is doing the same. After doing extensive internet research, I found that most mechanics and DIYs refer to the alternator. I removed it and had it checked at Autozone. They insist it is functioning well. The alternator itself has a rust color around the clutch area and it makes a humming noise as well. I feel like replacing it but new is around 300 retail. My next move would be to take it to an electrical mechanic for their input. Any comments/recommendations are welcomed. Thank you in advance and no thanks to Autozone....