Shaking/ stuttering when accelerating

[Leisah]

Hello,
I have a 2012 Subaru Impreza 2.0i-L MY2013 Sedan in Auto, 82k. Bought it 1year 6 months ago with 76k. I’ve notice a bit ago sometimes when accelerating that the car shakes back and forth/ stutters, it always seems to always happen when I slow down then accelerate. Speeding up on a freeway the car stutters then launches. A family friend who is a mechanic, specialises in Subarus has checked everything and said everything seems good. Recently done an engine flush. He’s pointed out that my front tyres and back are different (bought it with those tyres).Yesterday I took my car in to a tyre place to see if it was a wheel alignment issue, they also pointed out the tyres. Car drives a lot smoother since but the issue still persists. Had an issue a week ago when it was raining heavily, I was turning on a peak on a steep road onto flat road and my car spun out causing the electronic stability control to turn on. Back tyres are Dunlop SP Sport 01 205/55R16 while the front is Habilead Headking 52000. I am getting new tyres tomorrow. Just wanted to know what else I can check? Thank you!

 

[Ecmbuster]

Older post but also meant for future readers:
Tire circumference is extremely important for all the controllers that read speed / rpm.
The relationship will be with the ABS system and Traction Control. Speed differences within the two systems and the 4 wheels will create a "contradiction". Tire quality is also a factor.
it can take one incorrect tire (tyre) circumference to have one or more safety systems misbehave.
If the 4 matching tires have been installed, most of those issues may not present themselves.

 

[Leisah]

Thank you for the response. I got the tires changed and it didn't fix the issue. Doing an Idle reset fixed it.

 

[sheikh2]

Thanks for sharing the solution, Idle reset... such an unusual thing to me.