2001 windstar with 70,000 miles while driving noticed check engine light. After that was just driving down the road the engine completly shut off two times. However the van starts back up and runs fine. Autozone checked and got 02 sensor. Personal garage got lean fuel code and fuel filter has been changed since light stayed off for about four days and now back on.
Could this possibly be a dpfe sensor.

 

There is a TSB to replace the port o-rings and isolators on the intake plenum. I have done hundreds of these at work. Your codes were p0171 and p0174, correct?

 

I will have to get ahold of my friend to confirm the codes I also looked in the tsb index and cont locate the tsb for this problem. I will let you know when I find out thanks for all the help

 

In all my experience with OBD-II engines, anytime I get the "lean bank #1" thingy, it's the O2 sensor.

I don't know about the Windstar, but the Explorers and Aerostars have only one set of O2 sensors, hence only one bank. There is no bank #2.

 

The windstars have 2 sets of sensors, so a bank code is valid. Try replacing the sensors on that side. If that doesn't work, look for a vacumm/intake leak or an exhaust leak. Then move on to plugged injectors or bad plugs.

 

the shape of emissions things to come
multiple O2 sensors on engine exhaust systems
next will be single O2 sensor on each cylinder
some of the new lux buck vehicle O2 sensors for V6's with 4 sensors total over $3,000 to replace the lot with dealer parts
so much for low cost maintenance

 

Uhm where did you get this information? All my information says this will not happen, the reason the Buick has 4 sensors is because the buick has 2 converters on seperate banks. The Windstar is the same. The reason the sensors on the Buick cost so much is because it is a Buick and 2 of them are not O2 sensors.

 

Well, we did go from a carb to one injector per cylinder. Nothing will surprise me

 

WE went to multiport injection because throttle body injection was as bad a a carb. You don't want to measure the fuel air at each cylinder because it would make the systems overly complicated, and controlling catalyst efficiency would become more difficult. You would also add more weight to the vehicle, and increase cost. TB injection had most of the same problems as a carb. I would not atomize properly, the fuel would lag (you want it as close to each cylinder as possible). There are not any designes that would suggest that they would use that many sensors, especailly since todays fuel air sensors can detect a change in the mixture so fast that the computer knows what cylinder the exhaust gases it is measuring came from.

 

Back when I worked for the EEC group at Ford, we saw early designs for the EEC-IV computer that showed some pretty advanced features, such as port-timed fuel injectors and an EGO sensor on each cylinder. The EEC-IV computer is capable of deploying this, but the cost would have been too great; EGO sensors cost us $80 a piece from Robert Bosch at that time. So the decision was to go with one on each bank to measure average O2 content. To time the exhaust pulses to determine which cylinder produced which puff of smoke would have required precise knowledge of the individual patchs from each cylinder, and some way to keep the gasses from mixing. That just wasn't practical back then; it would have been easier to install individual sensors.

We had just started to release the TBI systems, which were worlds better than the variable venturi carb in use at that time. It used electronics to control fuel injection, instead of airflow to suck fuel out of jets. The problem it shares with carburetion is that, assuming you sensed the air pressure properly to inject the right amount of fuel, you're still depending on the fuel to reach some kind of steady state ratio in the intake manifold. There is always a lag between what the cylinder needs and what is available in the manifold.

Port injection provides much finer control, but it's still far from perfect. It's still relying on the average fuel/air ratio at the port to supply the need of the cylinder, but the response lag is much shorter than with TBI or carb. Then with the bank injection that many of our Aeros use, there is always some amount of liquid fuel build up behind the valves. That's a step backwards compared to timed port fuel injection.

The ultimate solution would have been direct injection. Ford had at that time some experimental engines called PROCO (programmed combustion) that utilized this design. They were very complicated then, and I'm sure they're even more so now. Except now, we actually have the computer technology to practically implement it. (I think there are a few passenger cars being sold today with GDI engines.) Back then our computer took up the entire passenger seat and footwell, and needed 4 extra batteries to keep it going.

 

NASSCAR is already using multiple O2 sensors, up to 8 for V8
even wide band high speed O2 sensors can only read O2 changes every 100ms....far too slow for exhaust pulses at 2k rpm=6k exhaust pulses per minute in a V6 single exhaust, 100 per second, one every 10 ms

even 1 wideband O2 sensor per cyl. exhaust will only be able to average over several exhaust pulses at high rpm

we will see these fast O2 sensor air/fuel mix systems first in the lux. high performace car field, the Italian and German super road machines such as Lamborghini. Maybach, Mercedes very top machines AMG S65 and the top end BMW V12 760LI
better engine air/fuel management equals more horsepower while still meeting strict emissions regulations

the days of indirect injection in the head runner are numbered. direct injection into the combustion chamber is already here in production street cars

http://www.forparts.com/bosmotorsports.htm

 

Thanks, Khan, Eugene and Cliff for the explanations. I learned something today.

 

In anay case, your Windstar has seperate O2 sensors for each bank. So if you get a lean code on one bank, it means either that bank is really lean, has too much oxygen entering the exhaust stream, or you have a bad O2 sensor. Possible causes for lean would be a plugged fuel filter, a plugged injector, or a vacuum leak. Possible causes for too much oxygen entering the exhaust is a bad exhaust gasket, a crack in the pipe, a crack in the manifold, or a poor manifold to head seal. A bad O2 sensor is self explanatory.

 

The O2 sensor (along with other engine sensors) monitors oxygen content in the exhaust gas & uses this info to calculate & command fuel injection pulse width, which will maintain the air/fuel ratio at approx 14.7 :1. This is how the fuel trim is initiated. The O2 sensor does this by sending a small voltage to the EEC computer. This voltage alternately switches between rich & lean at about 0.5 volts. A rich reading is sent to the computer at .8 volts & lean switching signal at .2 volts. If this switching mode is not occuring during closed loop operation (warmed up engine), the EEC will throw codes & possibly the CEL will be commanded on. Usually when an o2 sensor fails, the system runs rich (less damaging to the engine), & of course fuel economy goes down the drain & the engine develops that infamous "woolly", bogging down feeling of lacking response..... especially when warmed up. Pull a plug on bank affected & check for black/sooty electrodes. Does your gas mileage suck?

O2 sensors also have a heater circuit to facilitate quicker warm up & better fuel efficiency, since proper operating temperature is essential for correct operation. It certainly looks like you do have a failed o2 sensor. I would definately check out the wiring connection & replace the sensor. They are generally good for 60,000 miles & Ford recommends replacement at this service interval.
HTH, Aeroman59.

 

I changed port o rings and isolators on intake plenum. Reset comput and she is running great Oh and that was the codes I got thanks again AERODUDE and everyone else who replied.....