What should you do if your engine sounds like it is knocking after you had a very minor accident that only scratched the bumper and did not make a police report?

Find out what is causing the knocking, more than likely this is not related to the accident, and simply a coincidence. If the shop feels it is accident related, then have them (or you) contact the adjuster and advise them of the same...Do not put this off, harder to get understanding if you call the adjuster and say, ''my engine is making this noise and has been for six months since the wreck'' ......... rather than immediately after finding out, you can understand that.....