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car throws code.. whats wrong?

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Old Jun 18, 2006 | 05:53 PM
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Default car throws code.. whats wrong?

hi my car is throwing the code P0300 (multible/random misfire) any idea whats wrong?
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Old Jun 18, 2006 | 05:56 PM
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it would be nice if you would tell us what mods you have, just stating your car has codes does no good.

check spark plugs, spark plug wires....etc at first
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Old Jun 18, 2006 | 06:04 PM
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My car has thrown that a couple times over the years - just cleared it and doesn't come back. If it's persistent something else is going on.
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Old Jun 18, 2006 | 06:20 PM
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Originally Posted by 2001NBMZ28
My car has thrown that a couple times over the years - just cleared it and doesn't come back. If it's persistent something else is going on.
well it randomly comes on and off. the car idles a bit strange when fully hot thoug, but not to serious. the only mods known to me is an aftermarket exhaust and K&N filter (it realy dirty if it matters) and thats about it...
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Old Jun 18, 2006 | 06:32 PM
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I'd clean the filter and do a plug change.
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Old Jun 18, 2006 | 06:33 PM
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check your spark plugs and wires... how many miles on the car?
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Old Jun 18, 2006 | 07:03 PM
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78k miles 99model
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Old Jun 18, 2006 | 09:05 PM
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have the plugs ever been changed?
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Old Jun 19, 2006 | 07:46 PM
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i dont know i just got the car and i have no service record of it. but just receved my power programer last night and it the car hasnt thrown this code for some time now after i set the engine up for premium fuel
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Old Jun 19, 2006 | 10:15 PM
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like i said... change your spark plugs

i recommend NGK and they sell them at advance auto parts

whether it is set up for premium fuel or not that won't matter
it will take a good 1hr or more of driving and different driving manners for it to set any other codes

I highly recommend changing your spark plugs. again NGK's are at Advance Auto Parts just tell them the make and model of your car and they will look up the model you need, also once you get them ask the guys at advance if they can check each of the gaps on the spark plugs for you ( i think they should be set at .05?? or .055??, can't remember right now)
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Old Jun 20, 2006 | 12:03 PM
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thanks for all your help i apreciate it. we dont have advanced auto here in iceland but ill be ordering better plugs and wires in the future.

on a side note though ive been driving all day and all last night and it hasnt thrown a code yet. if i were to guess id say that the things that are changed by the computer patch up the alredy worn cables and plugs and give them a few more miles but you are probably right about that they are begining to go bad
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Old Jun 20, 2006 | 10:42 PM
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no problem, since it has 78k miles i would suggest changing them as if they haven't it is time. hope it all works out
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Old Jun 20, 2006 | 11:52 PM
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Do you still have the EGR valve? If that was sticking open it whould have a weird idle.
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Old Jun 21, 2006 | 04:25 PM
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culd be. it idles a bit strange but has been getting better.. actualy the car has been getting better since i began to drive it... its newly imported so it hadnt been driven for one month or more so that may have something to do with the idle..at least its just fine now
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