Diagnosing Hesitating/Misfiring X35i with No Codes

[andrewwynn]

I use Lucas. I forgot about D.I. that model. I mostly only work on e53 models. What I can say is that I chased similar studders and random individual cylinder misfires chasing like whack a mole on wife's car (replaced two coils and all plugs) before realizing could be dirty injectors.

I put in two bottles half a tank at a time (unsure why I didn't do two at once in a full tank). The problem went away and hasn't come back. I try to run injector cleaner at least yearly.

Quality gas has plenty of detergent shouldn't need it but evidence to the contrary it does.