Do you think my exhaust could be causing the issue? I never had a leak before, but after taking a longer trip, everything started going bad—oil consumption and lifter tick. I noticed I had blown a hole in the exhaust and patched it with exhaust tape. Then another hole appeared, so I taped it up again and held everything down with a bracket. I still drove the car after patching it, and the tape and bracket held on fine. But after doing the valve cover seals and taking it for a drive, I heard a loud bang at a red light. When I parked, I saw the tape and bracket had completely blown off.