Intermittent cylinder 4 missfire and breakup at peak boost

Hey guys, so I've been having some issues with my speed 3 lately and I'm struggling with figuring out what it is. So the car runs smooth at idle and during regular driving but as soon as I hit peak boost it breaks up really hard i also had a cylinder 4 misfire code pop for only a small period of time and then it dissapears. My compression is good at about 175 across the board with ~2% variance. I've put new coils and plugs in but it's still happening and I can feel a clear loss in power. Any ideas on where I should start?

 

Replaced with OEM coil packs? What plugs did you put in? What plug gap was set?

 

Yes they were oem coil packs straight from mazda, the plugs were NGK and I don't remember off the top of my head what # but it was happening even prior with the old plugs as it was running fine for a few months and then started doing this only about a week ago

 

It only takes 15mins or less to pull the plugs out to confirm type and gap set. Otherwise a data log would tell you a whole lot more what's going on.

 

Logs, need those logs. In theory it could be the PRV starting to fail but without logs it's just a shot in the dark

 

I'll pull the data logs for it, I just don't want to drive it too much as is.

Next time I get the chance I'll pull the plugs and update

 

Grab an idle and cruising log while you're at it.

I completely understand not wanting to drive it when it's acting funny

 

The plug gap opened up pull the plugs and regap