Glad you seem to have got it sorted! Thanks for posting back and letting us know.
Originally Posted by foaxaca
Embarassed to admit that after reading another post and looking in the Bentley manual it suddenly occurred to me that I may have flipped the leads for the O2 sensors and plugged them in backwards. Sure enough, switched them and the car idles perfectly. Will still change out the old plugs with identical replacements and forget the +4's for now based on what other posters are telling me.
1998 BMW 328is Shooting Brake
1966 Pontiac GTO
2007 Subaru Impreza 2.5i 5-door
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