Hello, i have a 1.8 2001 s40 with automatic transmission. Here is the problem:
While the car goes on the way(gear in D), when i release the gas pedal, sometimes engine acts like i put the transmision on 3 or L, its like engine braking. And rpm is waving. The car is fully normal on accelerate and stopping both gear in N and D.
I checked the shifter position sensor its ok.(Trying to start the engine while shifter isn't in N or P)

Do you have any idea?

(Sorry for bad language )

 

Try rowing the shifter (Park to Lo to Park 20x) to see if that helps. Also check the transmission fluid level, then check color (wipe the dip stick on a white cloth or white paper towel). Anything else going on ie blinking shifter up arrow or tracs light on?

 

Transmission oil level is ok and color is nearly pink and there is no smell like burned oil.

There are no faulty lights on. Everything seems fine.
But i discovered today that when i turn off a/c, problem is noticable reduced. But i didn't had time to drive the car on a long range for testing. I am watching for an opportunity for it.

I will try rowing the shifter.

And thank you for reply.