98 V70XC transmission operating & parking issue

[GEM-Massachusetts]

My son has a 1998 V70XC with 171,000 miles. We have owned the car since 2001 with 90,000 miles. After resolving the fuel pump matter from last May, a new issues has emerged. The transmission seems to be operating from a higher gear when starting from a dead stop (starting from other then 1st gear) or when accelerating (not downshifting when attempting to accelerate). This seems to be happening only periodically but then clears up and car operates normally. The transmission fluid appears to be at the proper fluid level.

Additionally, if the car is shifted into park when the transmission is acting up, the car will roll very slowly. We have watched the rolling action and it is almost imperceptible if not watched closely. The other night he parked the car and went into our house. The next morning I notice the car had rolled approximately 8 to 10 feet backwards down the driveway. I seem to recall that the car could have continued to roll further because it stopped at a point where the driveway is sloped. But the car could not have rolled much further. When the transmission is functioning normally, the transmission can be placed into “Park” and the car will stay firm. You can feel the transmission lock. When the transmission is acting up, you can't feel it “lock” when shifted into “Park”. Also, when the transmission is functioning properly, starting and accelerating are proper. Any insight will be appreciated.

[FlyingVolvo]

Sounds like a PNP switch issue. Does the "Up Arrow" light-up on the dash?

Next time this is happening, with the car on and your foot on the brakes, row the shifter quickly back and forth (all the way up and down) 15-20 times and see if it helps. If it does, you'll need a new PNP switch.

You fluid may be at the right level, but how fresh is it?

PS. Always use the parking brake.

[igel513]

Your tranny could be in Winter mode. It would start moving forward from third gear to avoid wheel slippage in snowy conditions. Do u have the 3 buttons below the shifter w/ letters E S W. Press Economy for normal driving or Sport for better performance/acceleration.