Engine Misfire

Check fuel quality.
Check EGR system. See SYSTEM/COMP TESTS article.
Check spark plugs.
Check ignition circuit. See CODE 14 in TESTS W/CODES article.
Check distributor.
Check water temperature sensor circuit. See CODE 22 in TESTS W/CODES article.
Check engine compression.
Check airflow meter circuit. See CODE 31 and CODE 32 in TESTS W/CODES article.
Check fuel injectors. See SYSTEM/COMP TESTS article.
Check cold start system. See SYSTEM/COMP TESTS article.
Check ECU. See SYSTEM/COMP TESTS article.