P0401,p0402,p1405,p0171,p0174,p1131,p1151 - 2000 Ford Windstar

P1151 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 2


p1131 p1151 p0171 p0174 p1131 p1151 p0171 p0174
All of these p1131 p1151 p0171 p0174 codes indicate a problem with a lean condition. This engine is known for vacuum leaks, so before you start throwing oxygen sensors at the problem, it pays to perform some diagnostics.
Start by cleaning the MAF sensor. Spray the sensor with CRC MAF sensor cleaner. Next, check the plastic vacuum lines, especially where they meet with rubber boots. If they are cracked or the rubber is swollen, replace the line. Then check the rubber elbow that holds the PCV valve. That elbow is a know failure point. In fact, the entire PCV tubing is a trouble spot on these engines. (thanks Ford).
After you've checked for vacuum leaks, check the operation of the oxygen sensors. The easiest way to do that is to disconnect the sensor from the harness. Connect one lead of your digital voltmeter to the black wire on the sensor and the other lead to battery negative. Then start the engine and add fuel (either propane, starting fluid, or carb cleaner) into the throttle body to force the mixture to rich. You should see a corresponding increase in voltage as you add fuel (from 0 volts to slightly less than 1 volt). Start and stop the fuel enrichment and watch the meter to see if the volts drop as you stop adding fuel. If you see no change, the sensor is dead. Replace it.
You can also use the fuel enrichment procedure to locate intake gasket leaks.
P1131 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 1
P1151P1151 Lack of Upstream Heated Oxygen Sensor Switch - Sensor Indicates Lean - Bank No. 2
P0174 system lean bank 2
P0171 system lean bank 1


This is the only info that didn't come back directly to FORD (yet still mentions it) instead of GM. Not to sure you got the correct code.

A good technican.

Autozone and some other auto part stores will scan for free and tell you what all the codes are/mean.

Go here and enter the fault codes in the Search OBD II codes.

All these are fuel trim codes and fuel control O2 sensor related codes, you have something that is causing this as all the sensors seldom fail. My advice here is to see a Ford dealer for the diagnostics before any parts are replaced.

you can look it up on "obdii" trouble codes web site

P1131 Lack of HO2S-11 Switch ,Sensor Lean
P1151-Lack of HO2S-21 Switch ,Sensor Lean
PO171- System to Lean (Bank 1)
PO174-Systen to Lean (Bank 2)

Fuel Filter -Plugged
Low Fuel Pressure
Evap System -Leaks
Leaks - in ducting,air filter to throttle
PCV -Leaks
Exhaust System -Leaks
O2 Sensors-worn out

p0401 egr flow insufficient. p0171 system to lean ( bank 1 ). p0174 system to lean ( bank 2 ). common problems that trigger p0401--

• Restriction in the EGR passages, usually caused by carbon buildup
• The EGR Valve is defective
• Lack of proper vacuum or electrical signal to the EGR valve
• Malfunctioning EGR Vacuum supply solenoid
• Lack of proper EGR system feedback to the computer from the:
  
  • Manifold Absolute Pressure Sensor (MAP)
  • Differential EGR Pressure Feedback Sensor (DPFE)
  • EGR Valve Position Sensor (EVP)
  • EGR Temperature Sensor - p0174--
  • In the vast majority of cases, simply cleaning the MAF sensor does the trick. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling also
  • Inspect all vacuum and PCV hoses, replace if necessary
  • Check for a dirty fuel filter and proper fuel pressure p0171- and p0174 are about the same.

Change plugs, and Mass Air Flow sensor. This should do the trick

it could but most likely not check for a vacuum leak check the hoses to the throttlebody the rubber fittings have a tendancy to get soft and collapse