Update: 1999 Honda Civic EX P0300,P0301,P0303,P1399 Misfire Prob

Changed all 4 spark plugs -- old ones seem not bad anyway. Rechecked plug wire set connection but did not change. Now it starts normally, seems ok whe accelerating with slightly noisier than before. But engine still shake slightly and idling speed fluctuate a bit once in a hile when idling -- seems still having misfire isssue. Asked a friend who do car repairing work and was sugeested to replace distributor cap/cover to see if this can solve the issue, otherwise may need  to replace the plug wireset (purchased new set but have not changed yet).

所有跟帖： 

• Here are the old spark plugs -blueisu- ♀ (87 bytes) () 11/15/2015 postreply 20:41:29

• 有没有机会测一下每个缸的压缩是多少PSI？当然了，先更换点火线、火花塞、清洗MAP、MAF、IAC、喷油嘴等 -饭得志- ♂ (0 bytes) () 11/16/2015 postreply 13:22:15

• Have not had chance to do other things -- will try to replace th -blueisu- ♀ (186 bytes) () 11/16/2015 postreply 13:38:10

• Misfire Problem seems to be fixed after changeing plug wireset -blueisu- ♀ (605 bytes) () 11/19/2015 postreply 08:39:30

• 谢谢反馈！如果先换线，其余都可以以后再做。 -周老大- ♂ (0 bytes) () 11/19/2015 postreply 20:28:47

• Yes. But the sparks plugs have been replaced for the past 9-year -blueisu- ♀ (204 bytes) () 11/20/2015 postreply 07:13:52

• Correction for the typo -- The plugs have NOT been changed for t -blueisu- ♀ (0 bytes) () 11/20/2015 postreply 07:15:14

• 最容易的法： -zhang88- ♂ (211 bytes) () 11/21/2015 postreply 11:57:56

• Thanks. 1999 Civic EX has 4 plug wires with different length so -blueisu- ♀ (191 bytes) () 11/21/2015 postreply 12:11:49