2017 3.5 pulsating at higher RPM

[prenticect]

I have replace MAP, cleaned MAF... my research has helped nada. it has been getting worse and no codes are thrown. best example, on the highway to pass. gets over 4k and it is like I am letting on and off the gas. any ideas? I asked before.. not any responses which means not many or any have this issue.

 

[99WhiteC5Coupe]

I have replace MAP, cleaned MAF... my research has helped nada. it has been getting worse and no codes are thrown. best example, on the highway to pass. gets over 4k and it is like I am letting on and off the gas. any ideas? I asked before.. not any responses which means not many or any have this issue.

Engine mileage?

Spark plug mileage?

Have you cleaned the throttle body bore?

Is the engine air filter clean?

 

[Timo2824]

Several different things can cause this, I would take it to the nearest competent shop and let a technician diagnose it. Mass air flow sensor, misfire, waste gate (it'd be loud though), less likely but the pedal position sensor/throttle body position sensors could theoretically cause this. They usually get an error code and go to zero though.

 

[Timo2824]

Clogged catalytic converters can cause weird issues above 3,000 rpm as well.

 

[Phillip Bradshaw]

I had the same thing happening on a 2012 expedition when idiling and it ended up being the throttle body.

 

[prenticect]

sorry, more details. 79k miles. plugs/coils replaced at 60k. air filter all good. throttle body rhe whole unit was replaced.. to replace the sensor it was a whole unit thing