u/Adorable-Sun-3896

I’ve have a 2016 Focus ST since new. Ever since new there has been occasional idle dips. (most frequent after refueling).

Basically sitting in neutral at a light, clutch out, RPMs dip randomly to about 800rpm, car sounds/feels like it’s about to stall, and then RPMs pop back up to around 1k

I know I’m not the only one that has experienced this, back in the day there were a number of forums posts about it.

Was the cause ever discovered?