I bought a audi a6 quattro, the previous owner said he hit a bump at 70mph and it screwed up the abs sensor so now the abs doesnt kick on and the abs light in dash is on. Could this just be knocked out of place, i know i need to fix the boot behind the right wheel, I had a friend who is very good at working on cars and said we just need a boot kit to fix that clicking. Any advice would be appreciated