When I worked as a wrench for Dodge, we sometimes would get different type of feedback noises off pressure hoses, whether it was A/C or P/S. The fix from Ma Chrysler was to put a 2-piece counter weight on the hose to change the dynamics. Maybe you can try a weight like the ones they have for kitchen faucet hoses that pull the hose back into place? Bolt it around the P/S pressure hose. Worth a try to unbolt from the sink to try it out, eh?

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