tt9714

1999 2.5L with 25k miles
check engine light ON with P1128 & P1130
smoke test at throttle body no obvious leaks
oil leak at crankcase ventilation valve & near middle oil filler tube
currently working to replace AOS, oil filler tube, and other vacuum connections

Macster

Why a picture of just 3? Why not all 6? No signs of excessive oil consumption, coolant contamination. With intake air leaks mixture can be running a bit lean. Different gasoline can affect plug color some.

To me I see nothing dire in the condition of the plugs.

Are you sure those are the correct plugs? I'm not familiar with the early 2.5l engine but the 2.7l engine at least MY 2002 took a plug with 4 ground electrodes.

The pic below is of one plug from my 2.7l engine. It was representative of the other 5. Plug probably had close 60K miles on it and IIRC that was the mileage at which they were to be replaced. All the times I had the plugs replaced in the Boxster the engine never once showed any real appreciation by running better. 'course, it was running ok before with the old plugs but still... However, this is kind of good news I think for it indicated that even with 60K miles the plugs were still quite up to the job.