luvdubs

My 19 year old son bought a 2006 ML500 and didn't bring me with him, so I didn't know what "we" were getting ourselves into. The power steering pump had just been replaced, he was told, it just needed to be bled. To say that the steering is stiff is an extreme understatement. My first two cars didn't have power steering and they were nothing like this. He's a burly kid, so he figured what the heck. Eventually he came to me and asked if I could help him get it sorted out.

We replaced the power steering reservoir, as there was a leak where it joined the pump. The indie mechanic that swapped out the pump just tossed the proper gasket and used a regular one.instead. I bought the correct gasket from MB dealership and a new reservoir. That stopped the leak, so I raised the tires off the ground and with the car not running went stop to stop 30 times. Let it down, topped it off, and started the car. Still stiff. I removed the pump and replaced it with a new pump then bled it again. No change. Ordered yet another pump and repeated the whole process. (I can now have a power steering pump off and in my hand in 12 minutes, by the way.) No change.

I don't know what to do next. The hose to the pump looks good; no obvious damage. The rack isn't leaking any fluid. I need help!

Dewey Dog

Try scanning the vehicle to see if it is throwing any codes of significance.

luvdubs

The only code he has is for a misfire on cylinder 3 (needs a coil pack)

Dewey Dog

I recently had my PS Pump/Reservoir/Rack all replaced and then had some issues with Clock Spring and Steering Angle Sensor. At this point, steering is fixed but now getting some strange deep whirring sound when I accelerate or when I go over a bump at slow speeds so will be looking into these items when I get back home from current trip.

Back to your issue, when my PS pump was going and the fluid was low, that is when I had the most difficulty turning the wheel as I drove to my mechanic. Sorry not more helpful.