One problem related to power steering light on has been reported for the 2009 GMC Acadia. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 GMC Acadia based on all problems reported for the 2009 Acadia.
When trying to steer the vechile below 5 mph's (engine below 1200 rpm), the steering wheel will lock up and is very hard to steer. My wife had this happen to her the first when she was pulling into our diriveway (thankfully it did not happen in the city). She told me about it, so I then took it to town shopping. It took a while before it happened to me, but finally it did when I was making a tight right hand turn into a menards parking lot. I started the turn and notice instantly that I had no steering. I almost hit another car because I was not able to steer sharp enough or fast enough for the right hand turn. After that, I got in the parking lot and did a little testing. I figured out that the steering was locked, and if the engine was reved over 1200 engine rpm, the steering would come back slightly. After several try's, it did come back. Dont know if I can trust it to work all the time??? it appears the problem is worse after the car has been run for a while. With cold temps it works until the steering system warms. , then problem is random. Scarey!!! feels like there is a flow control valve maybe that is in pump, and when it sticks open, the steering is lost at idle speeds. Not a good deal. . .