You probably have a vacuum leak. Check under the hood for a disconnected vacuum hose.
Trouble code P0171 means: Fuel System Too Lean (Cylinder Bank 1) Trouble code P0174 means: Fuel System Too Lean (Cylinder Bank 2)
p0171 andpo174 mean that you're car is running lean
Trouble code P0171 means: Fuel Trim System Lean (Bank 1) Trouble code P0174 means: Fuel Trim System Lean (Bank 2)
Trouble code P0171 means: Fuel Trim System Lean (Bank 1) Trouble code P0174 means: Fuel Trim System Lean (Bank 2)
Trouble code P0171 means: Fuel Trim System Lean (Bank 1) Trouble code P0174 means: Fuel Trim System Lean (Bank 2)
Trouble code P0174 means: Fuel System Too Lean (Cylinder Bank 2) Trouble code P0171 means: Fuel System Too Lean (Cylinder Bank 1)
Trouble code P0171 means: Fuel System Too Lean (Cylinder Bank 1) Trouble code P0174 means: Fuel System Too Lean (Cylinder Bank 2) These 2 codes are common indicators of a well-known failure on the 1999-2003 Windstars. Be sure to review the additional information in the "Related Questions" below...
lean bank 1 lean bank 2 fuel trim limits reached
Trouble code P0174 means: Fuel System Too Lean (Cylinder Bank 2)
Probably a vacuum leak. Do you have a code P0171 or P0174?
I'm not exactly sure about the 136 and 141 codes, but the 171 and 174 are symptomatic of a known problem with Windstar 3.8 litre engines. Those codes combined with rough idle are prime indicators of a leaking upper intake manifold involving worn out "isolator bolts". See "Related Questions" below for more
P0171-system too lean bank 1 and P0174-system too lean bank 2