Carbon buildup on the valves may illuminate the Check Engine Light, indicating "Multiple Cylinder Misfires." The combustion chamber must be cleaned of carbon. There are updated valve spring retainers that will help prevent a recurrence.Google+
Car Problem Reports
Dodge Magnum Check Engine Light Due to Carbon Buildup on Valves
Dodge Magnum Problem
Engines Affected: 2.7L V6, 3.5L V6, 5.7L V8 HEMI
Average Mileage: 162,500 mi (161,000 mi - 164,000 mi)
Visitor, 2006 Dodge Magnum, 2.7L V6, 161,000 mi
misfire cylinder 1, we replace coil, plugs and injector. just to find out this was the problem.