I want to know what is that.
Ford Q&AAsk Your Question
2003 Ford Windstar Question: my car has code p171 and p174
Answer #1milesauto from Miles Auto Service Inc., July 16, 2012, 08:19Master
Both codes indicate o2 sensors are staying at a low voltage theshold. Vacuum leaks on this engine are common. Upper intake manifold grommets and bolts have a update design to combat this problem. Have a reliable shop check your car for this.