It is possible one of the components driven by the belt may be partially locking up. Any component lockup would cause you to momentarily loose the power steering. These components include the power steering pump (not that a likely suspect as we have had very few fail or lock up) the alternator, air conditioning compressor, the idler pulleys, water pump, faulty auto belt tensioner, worn or stretched belt. We have also had water leaks or oil onto the belt that caused slippage. Sometimes a leaky water pump.If this happened to you just once it may be hard to diagnose. We usually remove the belt and check the components for binding when they are spun by hand. If you do not feel any binding at these components you may have to wait until the condition becomes more obvious.

