My car seems to sputter sometimes recently under full throttle/full boost. I loosened the wastegates slightly to lower roll on boost as I was seeing 1.3 BAR recently due to the recent seasonal temperature drop.

The target is 1.1-1.2 BAR

Same facts:
New MAF about 1,000 miles ago
Plugs are 17K miles old
Car has 26K miles
91 Octane GIAC flash
No CEL
I don't have a logger

Any suggestions?

 

plugs or coils. most likely plugs.

 

could be on the fuel side...pump, filter, injector...

 

I noticed you said you did not have a logger. My advice: GET A LOGGER--- you really need to get the codes otherwise you are pissing in the wind

 

Car is probably running rich. Check plugs

 

Probably the plugs.....17000 miles is too long for a tuned 996 turbo ,they should be changed every 10,000 miles.

 

Spot on.

 

plugs it it happens at around 4500 rpms....

 

That's about right Markski.

Doesn't a few overboost sessions blow out plugs? It's amazing how 20-30 degrees makes a diffrence in how much boost you run.

BTW I owe you a free year phone service. PM me for details.

 

I noticed the same( but i am 100% stock ) got new plug and good as new.

 

boost leak or replace plugs and check for coil pack(cracked)

 

Got it fixed. Loosened the aftermarket wastegates a bit and now I'm boosting 1.1 - 1.2 1.1 up the rev range.

No more sputtering. Just tire spin through first and second

 

Glad to see it fixed.