ANYBODY RUNNING INTO LATE MODEL FORD EXPLORERS WITH 4.0 ENGINES WITH DTC'S PO171 AND/OR PO174 STORED. THE LFTRIM IS REACHING IT'S LIMIT CAUSING THIS CONCERN. I HAVE HAD IT ON BOTH BANKS AS WELL AS ON ONLY ONE. THE O2S ARE RESPONDING WITH PROPANE ENRICHMENT. NO... Login to read more.