Is there a way to bypass the power steering assist?
No, Have the system looked at by a mechanic ASAP. Could be the PS assist module, rack and pinion or steering column. Not safe to drive.
You could pull the fuse although that might disable other electrical components of your car. Not sure if the power steering is on a separate circuit, but it probably is. Not sure why you'd want to do that though.
Missed the last part of your post... Mine does that too occasionally and then goes away again, making it very tough to diagnose. Let us know what you find the problem to be.
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