if you have a noise... a crashbar most likely wont resolve it, it just isnt the same design as the stock bar(probably only a little extra stability). But you tightening your front mount could help... just back track anything new you added to the car and what was taken off and replaced. Plus, whats the mileage on your car because if you go through your manual and the check-ups, at certain points things need to be retorqued for this very reason.
plus jay has a point, paranoia plays a roll... you add something new and your weary of the outcome and effects.
ps - when was the last time your car had a realignment?(you've probably been to the track recently which is a lot of stress on the frame) Bad alignment mixed with the removal of the crashbar could do it too?
its all about trial and error.