CEL and weird bucking?

[jtimms6]

Recently picked up a stock 06 ms6 with 140k on it the car Is clean in and out and hasn’t no problem until now at idle the car is fineness runs smooth with no noise isn’t missed but as I left this morning the car started to buck around 1/4-1/2 throttle and threw a p0301 code which Ian corn a missfire however not sure where Tom look or what to check since it isn’t a plug or coil since it doesn’t miss all the time. Unless it could be a intermittent coil/plug it just seems to consistent let me know what you guys think it may be. Only other thought would be a boost leak? Would that cause this I’m not sure any help would be great thanks!

[jtimms6]

Recently picked up a stock 06 ms6 with 140k on it the car Is clean in and out and has no problem until now at idle the car is fine and runs smooth with no noise and doesn’t miss but as I left this morning the car started to buck around 1/4-1/2 throttle and threw a p0301 code which is a missfire it does it mostly in 2nd to 6th gear. It did it once last night as well but then stopped and didn’t do it again until I drove this morning however not sure where to look or what to check since it isn’t a plug or coil since it doesn’t miss all the time. I can rev the car in neutral and it won’t mis shake or run rough only happens while I’m driving the car and it’s under boost.Unless it could be a intermittent coil/plug it just seems to consistent let me know what you guys think it may be. Only other thought would be a boost leak? Would that cause this I’m not sure any help would be great thanks! Sorry had a lot of missed info and it wouldn’t let me edit***

[Db09ms3]

Tune up. It's cheap and easy, will also get you acquainted with your purchase.

[Fstrnyou]

Any time I buy a car I go through all the standard maintenance items change fluids inspect brakes plugs filters consumables I even pull the seats out to vacuum and scrub clean what remains from the previous owners It's amazing what you'll find sometimes.

[jtimms6]

Sounds good when I got the car I did an oil change and a cold air intake also updated the Cobb tuner and tunes and reflashed the car after I got it inspected so I guess I’ll do new plugs and go from there see if that fixes the problem thanks

[Db09ms3]

Yeah that isn't a tune up. Plugs should've been inspected, replaced just 'cause, and gapped along with your 1st oil change. Clean your MAF sensor too while you're at it.

[jtimms6]

Update: so I went and put in 4 new plugs looked like they haven’t been changed in a long while cylinder 1 looked the worst gapped them to .30 iridium plugs also cleaned the MAF sensor when I did the intake drive about 60 miles today and never had that problem come back even after the car sat for a couple hours and was cold which is when I was noticing it the most so hopefully that’s another problem solved thanks for the help!

A follow up question however noticed two things first thing was I noticed that the most boost I get is around 14.5-15 but the tune says target is 16.5 is that normal for stage 1+ tune with a cai or should I be looking for something like a small boost leak? Also realized there was some oil on the cold side of the inter cooler not tons of oil but there was enough that I could see it inside the coupling to the throttle body...once again is that normal from an older car or should I be saving to get the turbo rebuilt? Thanks any advice would be appreciated!