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Engine idle

Turbong

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I have not been in another EB so I cannot compare, do these motors idle somewhat rough as in not very smooth? Hard to describe but its subtle sometimes shaky, stumbly (AC is off) nothing too obvious but you can feel the vibrations, its inconsistent. I have checked the plugs (stock) they seem to be gaped evenly within spec.
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jbailer

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Pull your spark plugs and re-gap them. Ford does a really bad job at the consistency of the gaps. Just gap them to stock, I think it was .030? Make sure they are all the same.
 

TheLion

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I have not been in another EB so I cannot compare, do these motors idle somewhat rough as in not very smooth? Hard to describe but its subtle sometimes shaky, stumbly (AC is off) nothing too obvious but you can feel the vibrations, its inconsistent. I have checked the plugs (stock) they seem to be gaped evenly within spec.
Yes it is fine unless the whole car is shaking or your getting misfire codes etc. Most 4 cylinders have a bit of a rough idle due to the timing necessary in a 4-cylinder configuration vs that of a V6 or V8.

HOWEVER, most 4-cylinders are transversely mounted, not longitudinally mounted (aka most are FWD, not RWD) like in the mustang. So the you won't feel the rough idle in the same manner which masks it a bit for your average passenger car, at least the ones I've owned.

AC makes it much more noticeable, normally I can feel it through the shifter every so slightly, but with AC on it's much more noticeable. Check your plug gaps as suggested, but even then your still going to notice it somewhat. Some people aren't as hypersensitive as others, so what feels smooth to one person may not to another. I happen to be one of those hyper sensitive people :D
 

mogo91617

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Someone saying its due to the bad xhaust mounting bracket near the transmission. Try mess around with it, see if the vibration resolved.
 

Cardude99

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I don't notice any roughness to my idle. I have an 18 if that makes any difference
 

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rvercitypony

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I have not been in another EB so I cannot compare, do these motors idle somewhat rough as in not very smooth? Hard to describe but its subtle sometimes shaky, stumbly (AC is off) nothing too obvious but you can feel the vibrations, its inconsistent. I have checked the plugs (stock) they seem to be gaped evenly within spec.
We both have a 2016 model. My car, before and after modding has always had a rough idle with occasional stumbles, after a cold start. Once it's semi-warmed up, the car idles smoothly--at least for a 4 cylinder motor.
 

KewlWinter

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We both have a 2016 model. My car, before and after modding has always had a rough idle with occasional stumbles, after a cold start. Once it's semi-warmed up, the car idles smoothly--at least for a 4 cylinder motor.
Check the fuel vapor purge valve. It can cause rough idle, stumbles, even cause the rpm to dip low around 500ish then recover when coming to a stop. Its easy to check, under the top engine cover, and if you find it to be bad, only about $30 and 5 minutes to replace.
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