Rough idle after new coil packs & plugs

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haggie126

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have a 2017 v6 eco boost, replaced all 6 spark plugs & coil packs. Plugs were gapped at .032
It still has a rough idle to it, and has no get up. After hitting 3rd gear it seems to improve significantly.
Trouble shooting done so far:
-Pulled wires while idling to check if any deceled (change in idle with all but 2)
-Unhooked battery
-Codes being thrown say misfires on all 6 cylinders
-Let idle for 15 minutes
-relearn the ecu
Before we start throwing money at all sorts of things is there anything we should be looking at specifically? Thanks
 

99WhiteC5Coupe

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have a 2017 v6 eco boost, replaced all 6 spark plugs & coil packs. Plugs were gapped at .032
It still has a rough idle to it, and has no get up. After hitting 3rd gear it seems to improve significantly.
Trouble shooting done so far:
-Pulled wires while idling to check if any deceled (change in idle with all but 2)
-Unhooked battery
-Codes being thrown say misfires on all 6 cylinders
-Let idle for 15 minutes
-relearn the ecu
Before we start throwing money at all sorts of things is there anything we should be looking at specifically? Thanks


Did you use OEM Motorcraft plugs and coils?

Why did you replace all six coils?
 

LokiWolf

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have a 2017 v6 eco boost, replaced all 6 spark plugs & coil packs. Plugs were gapped at .032
It still has a rough idle to it, and has no get up. After hitting 3rd gear it seems to improve significantly.
Trouble shooting done so far:
-Pulled wires while idling to check if any deceled (change in idle with all but 2)
-Unhooked battery
-Codes being thrown say misfires on all 6 cylinders
-Let idle for 15 minutes
-relearn the ecu
Before we start throwing money at all sorts of things is there anything we should be looking at specifically? Thanks
Like was asked above, what plugs?

That is the OEM gap, and on most 3.5's I see smoother idles with a tighter gap even with Stock tuning. That being said, sounds like you have another issue.

Did the misfire exist before the replacement, and you were hoping the plugs would help?

Can you post all the codes you are getting?
 

JVinOlathe

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Firing the parts cannon is never a good idea, you waste money and don't solve the issue.
If you are at the limit of your diagnosing capabilities, take it to a competent mechanic, have it properly diagnosed, and apply the correct fix. Much cheaper in the long run.
Unfortunately, the newer the car, the harder to diagnose issues. Many require specialized equipment that is prohibitively expensive to the non professional. A friend of mine that owns a shop pays over $6K a year to keep the diagnostic software up to date.
 

cmc3

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If you have FORSAN reset the engine control module. Also check for misfiring cylinders. Could be the coil packs didn't seat correctly or are NFG.
 

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