Here is my issue :

Aug, 2008, ~55k: Discovered rack leaking, and didn't want to front the money for a new rack. Used about a quart of fluid every six months so I decided to live with it (rack seeped fluid through the passenger side boot).

Nov 2010 ~94k - drive home from work with no power steering. Started car, steering was dead. Bummer. Next day, started it up, all was good.

Around March, 2011: finally replaced my leaking rack. Also found my cooling fan wasn't working - one of the plug leads had broken. A crimp and new section of wire fixed the issue. Perhaps the passing of winter kept me from frying my pump.

May 2011 ~108k - same issue - no power steering. Random occurance that I started my car, had zero power steering assist - drove it back from NH to PA. Next day, perfectly fine again.

Current ~124k - As of yesterday, power steering intermittently works. From a cold start it works great. As the car warms up, assist gradually declines to about 1/2 pressure, and sometime to zero assist. I have checked the fluid, and the level is fine. From a stop, if I kind of saw the wheel left to right, I begin to gradually build assistance almost up to the normal steering amount.

Hypothesis: Honestly, it feels like the pump is starving for fluid, or the electrical assist is not making a good connection. I have looked into buying a new p/s reservoir, as there is a "lifetime" filter built into it, and I figure if that filter is clogged, my pump may be starving for fluid (Hey it's only $50 + fluid).

Has anyone ever changed their reservoir or had a feed/starvation issue? I know I have had intermittent on/off operation of my pump in the past, but it seems like the motor is pumping strong, just maybe weezing to get fluid.

I have been cheating death with this pump for some time now, (since the intermittent complete failures and pump fault codes) but could really use the borrowed time if theres a temporary fix.

Any ideas?

 

Depending on how much work you want to do, you could pull the pump and look a the brushes. Apparently one of the weak points of the pump is the brushes fail but the rest of the motor is fine. Some old posts even showed just blowing out the dust from the brushes made the motor work for a while longer. Other posts they replaced the brushes and reported they were good to go.
If your labor is not a concern, give it a try.

 

Is there a documented thread on changing out the brushes?
Thank you.

 

Not so much a documented thread but just tons of posts about pump failures.
Even the people who replaced brushes did it with non-MINI parts. Very resourceful people.

 

I will check and advise, brushes sound plausible but the armature may need some work if thats been arcing. Will post my findings, scanning for codes now.

 

Looks like the fault code is 5508, invalid motor current. Tried the search and no results. Will check the leads and report my findings.

 

Last night, pulled the pump cooling fan, and the two electrical connectors. No signs of corrosion (was previously packed with dielectric grease.) fuse box was all good, no corrosion or any other funny business. Pump harness also looked perfect, no rubbing or abrasions anywhere.
At the moment I am sold on the brushes theory. Before assembly, I gave the pump a few gentle taps with a soft hammer. I have not yet lost power steering completely, but last night and this morning it is still sketchy.

Good news is that I found a company called modulemaster, which rebuilds the electrics for $225 (not counting postage), and they warrantee their work for five years. As that is the cheapest, as well as the most stable (given the five yeas warranty), I believe that is what I am going to do. Only bad news is the one week turn around time as they are in Idaho and I am in PA!

I'll keep this thread updated.