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CODE P0300 random/multiple misfire. what do i do?

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  #1  
Old 01-22-2009, 02:33 PM
Armenian's Avatar
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Angry CODE P0300 random/multiple misfire. what do i do?

hi, this morning i went to start my car and it sort of had a rough start and kinda shaky and the check engine light came on i drove for few miles to school and back and i park the car then started it up again the check engine light was off, i took it and got the code reader at the auto part store and the codes were: P0300 random/multiple cilinder misfire
P0303 cylinder 3 misfire
P0304 cylinder 4 misfire
i erased those codes...what do i do now?
i had this happen on the cylinder 4 misfire back couple months ago and i replaced all 4 spark plugs and it was fine. now here it does it again. what do you think its from or what can i do?

THanks allot guys
 
  #2  
Old 01-22-2009, 02:38 PM
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def. the coilpacks. 90%+ of the time when u have a misfire is because of the coilpacks, very common problem. i had to replace to coilpacks a month ago bc of misfires. and since u did your plugs its def. not them.
 
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Old 01-22-2009, 02:56 PM
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thanks for the reply, i am not familiar with the coilpack thing is it something i can do myself, what is it? how much it costs?

thanks allot
 
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Old 01-22-2009, 03:05 PM
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very easy, its what sits on top of the spark plugs. im assuming you have a 1.8T? im pretty sure the 2.8 v6 has coil over plug as well, but not 100%. you just unclip them and take it out and put the new one in. the dealer charges $36 each for them but if autozone has some instock i think they sell them for $25-30 each.
 
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Old 01-22-2009, 10:02 PM
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yes sorry i do have the 01 1.8t, so i would have to replace all 4 of them or just those that are causing the misfire?
 
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Old 01-22-2009, 10:40 PM
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all of them, if you replace just the ones causing the misfire, the others will go bad soon and you will get another misfire code again...
 
  #7  
Old 01-23-2009, 06:44 PM
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is this something that need to get done asap or i can wait on it for a while?
 
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Old 01-23-2009, 08:48 PM
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well if you drive your car on 2 bad coils your basically running you car on 2 cylinders?
idk how its acting now but it will start sputtering and just misfiring all crazy and then the check engine light will start blinking...and thats not good...

umm yea dude its not really expensive, just do it asap....
 
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Old 01-23-2009, 10:23 PM
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that was the only time that it did it and now it seems fine, after i cleared the code it hasnt come on yet you think i should wait to see if it comes back on again and do all 4 of them ?
 
  #10  
Old 01-24-2009, 03:14 AM
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I'd do the coil packs as the last resort since they are the most $$$. Check your spark plugs first, even though you just replaced them not too long ago. Mine starts fouling every 3K miles and with new plugs, it runs beautifully. 3K miles later, I get random misfires and repeat process...

Pull your plugs out and see if they are fouled and have any oil on them. I have some oil on mine and I'm trying to see if eliminating the PCV system and replacing it with a catch can will help the situation.

As for your coil packs, before you go out and buy any of them, swap out your cylinder 1 and 2 coil packs to your cylinders 3 and 4 for a while and see if the misfires moved to cylinders 1 and 2. If so then that's a sure sign that you have bad coilpacks.
 


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