One problem related to engine clicking and tapping noises has been reported for the 2005 Honda Civic. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 Honda Civic based on all problems reported for the 2005 Civic.
K20a3 camshaft lobes have pits/galling on them. They make a loud ticking/tapping noise. Possible decrease in gas mileage, poor performance, and reliability issue. If left unintended could cause further damage to engine. Common problem with the k20a3 engines manufacture defect. Honda should address this.