I have a PO157 o2 sensor circuit low voltage code and the vehicle is not starting every time. Sometimes it takes several attempts to get the vehicle started. I looked over the normal items like the connections and loose vacuum lines but didn't see anything obvious.
2000 Chevy Silverado, with 5.3 engine. No other codes. Vehicle runs great once started, idles perfectly, and has great acceleration.
do a fuel pressure test. I would start there -esp as the colder weather arrives. Did you run out of fuel? Is there an exhaust leak? If you have a scanner look at fuel trims. Check the freeze frame for p0157. PS- vehicle is STOCK no oiled air filter etc?
what year make model engine trans and color... there are NO other codes or issues- just long cranking to start? Not much to go on suggest you check fuel pressure. Post the psi with reply