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Need Help with misfire

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Old Oct 14, 2007 | 05:34 PM
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Default Need Help with misfire

My car is throwing a p0306 which is a cylinder 6 misfire. The car starts and idles fine but it barely holds idle when i try to drive it. It starts to miss really bad. I checked the plug wire and it was on good so i dont know what the problem is!
Can anybody tell me what else i can check?
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Old Oct 14, 2007 | 05:58 PM
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I'd pull the plug and see what it looks like.
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Old Oct 14, 2007 | 06:29 PM
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Originally Posted by 2001NBMZ28
I'd pull the plug and see what it looks like.
Thats what i'm going to do tonight. I hope its something easy like that.
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Old Oct 14, 2007 | 10:49 PM
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clear the code, swap the plug with #4 and the wire with #2. If the code comes back p0304 or p0302 you know if it's the plug or wire. If it's still #6, swap the injector with another cylinder. If it's still #6, compression test. I bet you'll find that it's just a spark plug or wire though.
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Old Oct 14, 2007 | 11:34 PM
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Originally Posted by pdsq98gt
clear the code, swap the plug with #4 and the wire with #2. If the code comes back p0304 or p0302 you know if it's the plug or wire. If it's still #6, swap the injector with another cylinder. If it's still #6, compression test. I bet you'll find that it's just a spark plug or wire though.
Ok thanks. I'll try that. I just put the NGK TR6 plugs and MSD wires on about 2 weeks ago.
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Old Oct 15, 2007 | 08:39 PM
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Oh buddy,

I had a misfire on 6 for a while some time ago, and after messing with all the electrical components (coilpack/wires/plugs/injectors), I ended up taking my valve covers off and saw that I broke a pushrod on the intake valve in cylinder 6. So i replaced it and a little while later it misfired again on that side and again broke a pushrod.

Wasnt until now that I swapped out my heads/cam I saw all the damage the pushrod did... check these out

1. Broken pushrod


2. Broken lifter guide


3. Hollowed out the lifter


I'm sure if I attacked the problem and not driven around with the broken push rod the damage wouldn't have gotten this far...

So, if the electrical moving around doesn't do you justice, please just take that darn valve cover off and check out to make sure the pushrods are tight and ok. Its really easy to do and I'm no experienced mechanic.

Let us know how it pans out!

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Old Oct 15, 2007 | 10:18 PM
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Dimitry, i hope it isn't as bad as your problem. Today i moved the plug and wire around and cleared the code. So far the car is running normal. I drove it around the neighborhood. When something is wrong with the car i never drive it so it shouldn't get damaged like yours. Im going to drive it around tomorrow and see how it does. So far the code has not came back
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Old Oct 15, 2007 | 10:27 PM
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cool bro, good luck
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Old Oct 17, 2007 | 06:54 PM
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I've driven the car about 75 miles and it is doing good, so i guess everything is ok. Thanks for the help
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