# Cylinder Misfires

**URL:** <https://community.cartalk.com/t/cylinder-misfires/95657>\
**Category:** Maintenance/Repairs\
**Tags:** ford, f150\
**Created:** [September 14, 2016, 8:18pm UTC](https://community.cartalk.com/t/cylinder-misfires/95657 "2016-09-14T20:18:56Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![jaimelopez6918](https://avatars.discourse-cdn.com/v4/letter/j/bcef8e/32.png) [@jaimelopez6918](https://community.cartalk.com/u/jaimelopez6918)\
**Post date:** [September 14, 2016, 8:18pm UTC](https://community.cartalk.com/t/cylinder-misfires/95657/1 "2016-09-14T20:18:56Z")

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I have a 2004 f-150 5.4 Trition v8 and recently i had misfires on 5 and 6 come up. After I changed out the coils and injectors on all the cylinders the misfire would still come up. Im looking for some more help on where to go from here.

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**Author:** ![Mustangman](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mustangman/32/44130_2.png) [@Mustangman](https://community.cartalk.com/u/Mustangman)\
**Post date:** [September 14, 2016, 8:40pm UTC](https://community.cartalk.com/t/cylinder-misfires/95657/2 "2016-09-14T20:40:37Z")

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Did you replace the spark plugs as well? Since 5 and 6 are side by side on this engine, maybe you have a head gasket failing. You need to run a compression test on 5 and 6 at least but do them all so you know the total condition. Run a dry and wet test. If 5 and 6 are both lower than the rest, there is a good chance the head gasket failed between them causing a misfire.

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**Author:** ![jaimelopez6918](https://avatars.discourse-cdn.com/v4/letter/j/bcef8e/32.png) [@jaimelopez6918](https://community.cartalk.com/u/jaimelopez6918)\
**Post date:** [September 14, 2016, 9:51pm UTC](https://community.cartalk.com/t/cylinder-misfires/95657/3 "2016-09-14T21:51:49Z")

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I did change the plugs as well but ill try doing a compression test, thanks

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**Author:** ![db4690](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/db4690/32/2583_2.png) [@db4690](https://community.cartalk.com/u/db4690)\
**Post date:** [September 17, 2016, 2:45am UTC](https://community.cartalk.com/t/cylinder-misfires/95657/4 "2016-09-17T02:45:06Z")

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You might also hook up a noid light to #5 and #6 injector plugs and see if it’s flashing when the engine is idling

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**Author:** ![common-sense-answer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/common-sense-answer/32/716_2.png) [@common-sense-answer](https://community.cartalk.com/u/common-sense-answer)\
**Post date:** [September 17, 2016, 7:57pm UTC](https://community.cartalk.com/t/cylinder-misfires/95657/5 "2016-09-17T19:57:48Z")

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**@jaimelopez6918**

_ **“I have a 2004 f-150 5.4 Trition v8 and recently i had misfires on 5 and 6 come up.”** _

I take it that you got DTCs (Diagnostic Trouble Codes) that indicated those specifics.

If that is the case it could help if you let us know exactly which codes, too…

_ **CSA** _