I own a 1997 Mazda Protege with the check engine light on. The emission-related powertrain diagnostic trouble codes show P0100 (Mass Air Flow Circuit Malfunction) and P0170 (Fuel Trim Malfunction - Bank 1). What do these codes mean, and how can I fix them? Please provide guidance. Thank you.
Jeff, thank you for your response. I was out of town—what does MAF stand for?
Mass Air Flow sensor—it's located in the air intake snorkel just behind the air filter. Check the wiring and connections to it. Try cleaning the delicate wires using brake cleaner or an electronic cleaner. Be cautious, as these wires are fragile. There may be a wiring diagram in the engine compartment to help locate it. Good luck and please keep us updated on your progress.
Likely issues could be a faulty Mass Air Flow (MAF) sensor or a vacuum leak from the intake gaskets.