Re: 99 Winstar, Miss at low speed
I have same problem on my 99 Windstar. Codes 171 & 174. No other clues.
Today I just happened to find that one of the control rods on the IMRC (
Intake Manifold Runner Control ) was off and just sitting there. This
sits on the left side of the intake manifold (plenum) and in my model is
one control unit with two control rods (arms) going forward and rearward
to control the "butterfly valves". Haven't yet got to it but you might
check yours. It might be the cause of the codes.