legenddriver2004

yes high HC's could be from a rich mixture but it is most commonly caused by a missfire due to weak ignition and all the preavious things i listed. and i was partly wrong about o2 but o2 will be higher then normal with high HC's. and dude nitrogen Oxid, oxides of nitrogen same thing. im mean come on man! and the highest NOx will be at or just past stoichiometry so 14.7:1-15:1 air fuel ratio, not your 17:1. by 17:1 NOx is falling back off. that is why an egr opens at just off ideal cruising which is when your air fuel is going to be in the 14.7:1-15:1 rang the most plus then you dont really need alot of hp. your just cruising unlike at idle you need all the power the engine is producing and same with WOT your useing all the power the engine can make. o and all my information is from the book "Automotive service" by Tim Gilles. Tim Gilles is a professor at santa barbara city college. he is also a ASE master technician and ASE master Machinist so i know my information is correct. The book is also supported by the ASE certification program and the NATEF. this is the book issued to every UTI student and wyotech student so im sure the information in this book is right. plus im ASE certified in basic engines, electrical fundamentals, and engine performace. engine performace just so happens to include emmision testing and emmision controle devices, so dont come telling me im wrong just cuz you see i have hardly any posts and im only 19. im not trying to be a dick, im just supporting my information i posted. o and i dont really care all that much about speeling, punctuation, and capitalization. im a technician not an english major!