mspa

We've got a 2000 Legacy "L" Wagon with about 94,000 miles. It is a 2.5 litre 4 cylinder with automatic. We've had all the 90k maintenance completed. But, we have a reoccuring shifting problem that we hope someone here can shed some light on.

What's happening is this: after the engine is warmed up, the engine will rev past the point when it should shift into the next gear. When it does shift, there is a loud "cla-clunk" noise and a lurching sensation. It also does the same thing upon slowing down (down-shifting), but not as severe. The weird thing is it that it will go days with normal behavior. Then without warning, it will happen again. The only constant is that it doesn't occur until after (at least) 10-15 minutes of driving.

We've taken it into the shop 4 times now for the same thing. Three of those visits, the shop could never get the problem to reoccur. The resolution on the first visit was replacing the external filter. Everything was fine for awhile. Then the problem started again. The second visit, the shop noticed the transmission pan was not all the way sealed. They replaced the internal filter, and put a new seal on. Yesterday, we took back to the same shop. They drove it. No problems. They ran it through diagnostics, to no avail. No codes to indicate any problem. Today we took to a transmission specialist. They couldn't find anything wrong and could not duplicate the "shifting" issue.

This is driving us crazy. Most of the time, the car drives perfect. There are no idling problems, no overheating. The "check engine" and "AT oil" lights come on when this problem occurs. I would think that should narrow the focus down to a couple of possibilities????

Any thoughts? It seems pointless to keep taking to shops hoping that someone will figure it out. To complicate matters, we are in the process of selling the car, which makes the situation more stressful, since we don't want to sell the car without fixing the problem.

mspa

Hey guys, guess what I learned?? We finally got the car to the transmission shop while it was acting up. They checked it out and told us a sensor in the transmission was showing a "low voltage" code. His advice was to get a new battery BEFORE replacing a $250 sensor—ours was in need of changing, but didn't even cross our mind! So it was an easy choice. Drove down the street, and $75 later I had a new battery in the car and the problem hasn't returned.

So the lesson I learned, was that as cars get more techy, they have more parts the need power from the battery . . . it was kind of like if your computer is not turning on, make sure it's plugged in! Well, not that bad I guess.