Hello,
I have a 2007 Honda Element LX with 372k mi. I have been getting P0171 error code (fuel too lean)for some time now. I have checked everything. Smoke test for vacuum leaks-pass, MAF sensor- Pass MAP sensor pass, new intake and exhaust valves, heads machined, valve adjustment done, throttle body- pass, O2 sensors-pass.
Symptoms at idle- rough idling almost bogging down the engine. Especially with AC load on. Almost misfire like symptoms at take off. Lastly did a fuel compression test and discovered the fuel pressure was irregular (not constant). So I put in a new fuel pump assembly and injectors. Everything seem great at first then hit 90 miles after install and the ****** P0171 returned. At this point I am out of ideas. Any suggestions welcomed please...