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Old 09-30-2013, 11:33 PM   #1
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Random Misfire of 2, 4, 6

Had a random misfire the other day while sitting at a traffic light. Check engine flashed for a few seconds and a little jitter, gave it gas and everything was back to normal and check engine light even went away.

Plugged in my reader and said it was a random misfire of 2,4,6. I was planning on changing my plugs this weekend anyways because I think it's about time.

Anything else I should check? Any reason why all of the driver side misfired at once?

Thanks

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Old 10-01-2013, 11:37 AM   #2
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Left-side misfire? Some might say happens every day in the White House.

Ok, joking aside, there are four primary causes of engine misfires - a loss of spark, an unbalanced air/fuel ratio, a faulty fuel injector or fuel supply, and a loss of compression. Obviously, there are a lot of components to consider. I'd change the plugs and see if you get a repeat.

If you do get a repeat, then look for components that are common to all of the left side cyls: left side intake plenum vacuum leak, left side fuel rail, left side exhaust leak or failed cat, etc.
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Old 10-01-2013, 12:06 PM   #3
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Cyl.#2 is middle passenger side. Firing order is: 1-6-2-4-3-5, so why did 3 cyl in a row misfire? As you remove sparkplugs inspect closely for variances that might give a clue.
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Old 10-01-2013, 02:00 PM   #4
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Quote:
Originally Posted by thstone View Post
Left-side misfire? Some might say happens every day in the White House.

Ok, joking aside, there are four primary causes of engine misfires - a loss of spark, an unbalanced air/fuel ratio, a faulty fuel injector or fuel supply, and a loss of compression. Obviously, there are a lot of components to consider. I'd change the plugs and see if you get a repeat.

If you do get a repeat, then look for components that are common to all of the left side cyls: left side intake plenum vacuum leak, left side fuel rail, left side exhaust leak or failed cat, etc.
Thanks for the detailed reply and places to check. I understand and know where to locate all of them, but where would the left side fuel rail be located and how would I check that?

Quote:
Originally Posted by BYprodriver View Post
Cyl.#2 is middle passenger side. Firing order is: 1-6-2-4-3-5, so why did 3 cyl in a row misfire? As you remove sparkplugs inspect closely for variances that might give a clue.
Middle passenger side? I thought all the even are on the drive side from front to back 2, 4, 6... but thanks for the firing order, you're right not only was it all on one side, but all in a row 6, 2, 4.. weird.
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Old 10-01-2013, 02:47 PM   #5
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Middle passenger side? I thought all the even are on the drive side from front to back 2, 4, 6... but thanks for the firing order, you're right not only was it all on one side, but all in a row 6, 2, 4.. weird.[/QUOTE]


#2 on pass side middle, #4 is driver side front, #6 is driver side rear. To maintain balance you have to fire one side then the opposite side.
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Old 10-01-2013, 05:07 PM   #6
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Originally Posted by ohhh my View Post
... but where would the left side fuel rail be located and how would I check that?
Fuel rail is the gold colored tube in the middle of the photo. Check fuel pressure and flow.

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Old 10-02-2013, 09:49 PM   #7
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edited.....

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