One problem related to manifold/header/muffler/tail pipe has been reported for the 2006 Honda Civic. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2006 Honda Civic based on all problems reported for the 2006 Civic.
Cracks in the engine motor behind the exhaust manifold and near the ignition which is causing a serious coolant leak. Plus, the a/c in the car won't start, but heat works.