This 2003 Ford Windstar came in with the service engine soon light on. Checking code revealed codes P0171 and P0174, banks 1 and 2 lean. I checked for vacuum leaks and none were found so I moved on to the Mass Air Flow sensor. It is common for them to get dirty and cause these fault codes. The MAF sensor is located inside the air filter housing so it had to be removed. I loosened both hose clamps and pulled the rubber boot from the throttle body and then from the air filter housing. Then I unlocked the spring clamp that holds the two halves together.
The crankcase ventilation tube also had to be removed from the rubber hose and more importantly it has to be put back in place during assembly. You can see it just to the left of the master cylinder.
After unhooking the wiring harness connector I took the housing to the bench for dis assembly. There are several locks that have to be released. I used a common screwdriver blade to pry them inward while pushing the sensor out from the other end.
There is also another wiring subharness that has to be removed. It is kind of a pain but I take my time so as to not cause any damage. Once the two halves were separated I removed the sensor from the housing using and tamper resistant torx bit socket.
This is were the actual sensor elements are located and in most cases you will find a build up or film on the element. I use a pick as shown or a small screw driver and very lightly rub the film off. Sometimes if it is heavy it will lift off in one try but most of the time it takes a little while of very light rubbing to remove the film. Some people use cleaners but I prefer to manually rub it off so as not to cause and damage to the sensitive parts. Many cleaners will damage the plastics.
Just several different pictures of the same sensor. There are two elements inside and the most problematic one is the one further inside that you cannot see.
This is just one of the possible causes. There are many and one of my readers left a link to a repair site that has more answers on this problem.
Ford has a TSB out on this for 1999 to 2003 Windstar. if you want to do it yourself, you need to go to your local parts store or dealership and ask for a “Valve cover repair kit”. This site link gives step by step instructions for the fix.
If the OBD2 unit you borrowed is only a code reader it will not do much good at this point. There are some companies that sell software and cables to turn a laptop into an OBD2 scan tool. They usually have limited abilities but are better than nothing. You would need to weight out the cost and time involved in trying to resolve the issue yourself versus taking it to a shop.
trbodden: I borrowed the obdII from my son in law but could get it anytime. How would i go about looking at the datastream? Would a note book pc help? After reading some of the results of trips to the dealer, I’m prepared to go as far as I can on my own. BTW, the odbII was only good up to the 2002 model but son in law says they’re pretty much the same.
There are of course many possibilities. The most common would be leaking intake gaskets. This generally starts with a poor idle condition when cold and will eventually degrade to a poor idle all of the time. Since you have provided codes, do you have the ability to read data stream?
Read you post with great interest. My daughter has a 2004 escape, 3L, that is giving codes P2195 (bnk 1, sensor 1), P2197(b2s1) both describes as lack of heated oxygen sensors,also P0171, P0174 , desc as system too lean bank 2 and bank 2 respectively. The car was stalling at idle and not too peppy.
After changing the fuel filter and turning the engine on it ran fine for a short time but started rough idling with rpm going up and down then stalled again. This with no foot on pedal. If I put foot to pedal and tried to hold it at 1000 rpm it ran smoothly. If this is not a proper post, lmk and I’ll post in proper place.Appreciate your comments.
Codes and some data would be a lot of help but I would suspect that you need to fuel pressure. Black smoke is an indication of a rich fuel mixture. If that is okay then look at engine and air temperature sensor readings.