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Did ATAP....Got engine misfire code P0300

Old May 23, 2004 | 06:25 PM
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Default Did ATAP....Got engine misfire code P0300

Did ATAP....P0300 code engine misfire? Multiple misfire's on all cylinders..
Did an ATAP via Jbrd400 (thank you again bro) And it told us that my car is misfiring...mostly on #8 but is happening periodically on all the cylinders. Also, I've noticed that right around 5k rpm it stutters REAL bad then will continue on to 6k if need be. The code it pulled was I believe P0300 said "engine misfire" I remember that for sure. I thought it was running REAL strong till we looked at with ATAP...anyone know why or what causes this stutter/misfire?? I have a stupid Jet chip in it that the previous owner had in there...could this be my monkey wrench???..A/F's were 14.0 , O2's looked good, NO KR, timing was right...so why misfire?


Just seemed to run so strong last night...I did get the SES light to flash racing the first civic yesterday only the 2nd time that has happened...it flashes the goes away....What's up with that?

Any input and advice is really appreciated!!

gatesfam33101@yahoo.com

Mike



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Old May 23, 2004 | 06:47 PM
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I would check your Valve springs. I had a nissues with valve float not to long ago and it had the same symptoms you describe. Also if you have a cam you will have to go and change the misfiure detection parameters if your springs check out. Have you checked all the plugs and wires?
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Old May 23, 2004 | 09:43 PM
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Car has 24k miles....no cam just basically stock with intake lid and 3" cutout...I thought about that valve float thing, it sounds just like it when I'm right at 5k...I doesnt happen every time but like every few WOT blasts it gives like a popping stutter right at 5k it'll also shoot like a backfire sound real loud out through the cutout...define misfire here someone...is raw fuel getting in the cylinder????
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Old May 24, 2004 | 10:11 AM
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Ditch the chip and try it again. also plugs and wires
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Old May 24, 2004 | 10:40 PM
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I'll losing the chip here, It looks like just a plug in type deal.
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Old May 26, 2004 | 11:50 PM
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Wow what was I on in that last post.....ANYONE ever have a misfire problem?? If so what the hell caused it??@???@???!??????!??!?
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Old May 27, 2004 | 07:02 AM
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fouled plugs from oil ingestion via PCV. Try new plugs.
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Old May 27, 2004 | 01:20 PM
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My buddy had the same thing going on.....ended up being a broken pushrod. He has an M6 also. After swapping plugs,wires, coil packs, decided to pull valve covers and check it out. Might want to check that if plugs don't cure it.

Good luck with it.
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