I'm not trying to high-jack your thread,
....... I have the same "service engine soon" .......
I have just changed my oil and filter, and also replaced
the spark plugs. The car has always run real strong, smooth idle, no mechanical issues. (battery cable removed during spark plug change)
soon after starting the car,
to check the oil. The service engine light came-on.
The car runs and pulls harder now then it did before. The old plugs were definitely worn and the gaps was worn to anywhere between 0.055" to 0.070".
new plugs were gapped to 0.044" per spec's.
any info would help ! Thanks...
2005 G35 sedan 96,170mi.