Anyone fix a P0171? I started out with P303 cylinder 3 misfire. Changed plugs and coil packs. Check engine light went away. 2 months later appeared. One week after that quit at stop light. Would not start. Replaced MAF. Started and ran with same P303 and later the P0171. Replaced injectors. Expensive. Same two codes. Car runs a little rough. Replaced O2 sensor. Nothing changed. Car drives but slight roughness when engine under a load. What’s next step? Thanks so much.
