As many of you know, we host a monthly contest sponsored by our friends at Federated Auto Parts. It's our "ASE Question of the Month" and we try to match it to the "theme" of our monthly issue. For August, our question was:
Technician A says the ECM's primary role in engine management is to ensure that the feed gasses being passed along to the catalytic converter are maintained in a very narrow range. Technician B says that the fuel trim data PIDs (Parameter Identifiers) represent corrections made to the injector "on time", expressed as a percentage. Who is correct?
About the Author
Motor Age Staff
Motor Age has been publishing technical content for professional automotive technicians since 1899. Our writers have decades of experience and scores of ASE certifications, and they continue to teach new generations of technicians via classrooms all around the globe, as well as through the books and training manuals they've authored.