Engine Intermittently Sputter/Misfires at 40+mph Thoughts

I have 2015 4 Cylinder. When i’m driving on the highway the engine will intermittently pause/misfire. I’m thinking it may have something to do with fuel injectors. Anyone else have thoughts on this?

Thanks!

 

How old are the plugs? Is there oil down in the spark plug tubes where the ignition coils sit?

 

I changed them at 100k Miles. I’m at 130k

 

Look down in there and see if one of the coils is sitting in a bathtub of oil

 

will do. what if there is?

 

Replce the valve cover gasket and tube seals (comes in a kit), replace the oil soaked boots on the coils or the entire coil

The concern is if the coil boots are soaked the rubber gets spongy and the spark arcs over to ground instead of going to the plug.

Have you seen a flashing check engine light at all when the problem happens? Have you scanned for codes? A misfire code may pinpoint a specific cylinder and help you narrow down the problem

 

My first gen was doing something similar recently- ended up being the fuel pump. Lots to rule out before jumping to that especially considering your low mileage, but always possible

 

Haven’t seen the check engine light which is why i also haven’t scanned for codes.

 

Get it scanned anyway, sometimes a code will be stored but for whatever reason the light never came on - or it was on very briefly and you didn't see it

You'd be surprised how many vehicles are driving around with current or history codes and the CEL just isn't on

 

Have someone check the long and short term fuel trim, my guess is that you have a bad upstream air-fuel ratio sensor (oxygen sensor). If it only happens when cruising under light load (minimal amount of gas pedal applied) then that would be a strong indicator. Also, bad AF sensors don't throw codes unless it's way out of spec or the heater circuit has failed. MAF is also a suspect, and again doesn't always throw codes, you'd need to look at the data values and compare to factory, in some cases. These are the two things I would look at for a no-codes stutter while cruising.