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
Chrysler Pacifica Check Engine Light Due to Carbon Buildup on Valves
Chrysler Pacifica Problem
Engines Affected: 3.5L V6, 3.8L V6
Average Mileage: 125,693 mi (65,000 mi - 178,000 mi)
CHECK ENGINE LIGHT COME ON...GOT IT TEST GIVE ME A CODE P0420
Visitor, 2006 Chrysler Pacifica, 3.5L V6, 65,000 mi
Engine Misfire, cylinder replacements, timing belt and water pump. $3900/ Called Chrysler they said not under warranty and cannot help with resolution.
my check engine light is on as well whn they get buildup like that would it cause my car to back fire and hard to start,put in a new fuel pump worked for 2 days and it stopped agian.or what would make my fuel pump burn out so quick
Engine light comes on and usually stays on. the Last car I brought with this same problem, I wasn't able to Pass the emissions Test.