Run fault codes and look for failed knock sensors. I would suggest that the rattling noise is detonation from a lean fuel mixture-ignition timing or faulty EGR system. Detonation is when the fuel ignites with out the use of spark and occurs early as the piston is coming up so the piston is slammed against the cylinder walls. Prolonged detonation will cause melted holes in the pistons tops and broken rings so I would advise you fix this problem as soon as possible.
Answers & Comments
Run fault codes and look for failed knock sensors. I would suggest that the rattling noise is detonation from a lean fuel mixture-ignition timing or faulty EGR system. Detonation is when the fuel ignites with out the use of spark and occurs early as the piston is coming up so the piston is slammed against the cylinder walls. Prolonged detonation will cause melted holes in the pistons tops and broken rings so I would advise you fix this problem as soon as possible.