2000 Windstar Engine Light

The engine light came on and according to Auto Zone the problem code is P0171, which they said could be an oxygen sensor, addmissions misfire/vacum leak, or fuel injector problem. My wife said yesterday when she stopped at a light the idle didn't feel right or sound right....as if it was trying to stall. She put it in neutral and pressed the gas a couple times and it seemed to be better. Today the light came on. Any ideas from what I have given as to which of the above possible problems it may be?
Thank you
John

How long can you drive with these codes? What will happen?

Normally this code (and its sister code 174) indicate a lean condition on one of the banks as measured by the O2 sensor(s). It could be the O2 sensor but most likely it is due to an intake leak or unmetered air in the intake. A 2000 (1999-2002) has a TSB that covers these two codes. Normally both codes will show up but perhaps the sister code will show up in a while.

Do some reading in this forum under isolator bolts, 171/174 or port seal for some background information. I would not rush ahead and do the TSB until you exhaust some of the other possibilities. You could swap the 2 O2 sensors from driver's to passenger's and see if the code follows the sensor or stays with the bank.

...and this is the procedure you'll eventually find when searching on this topic:
http://leckemby.net/windstar/windstar01.html

How long can you continue to drive with the 171/174 codes? What will happen?

You will probably waste fuel since the PCM is trying to compensate for a "lean" condition. It will possible cause you to fail emissions testing and it is bad for the environment.

The question is why would you not want to fix this?

You will probably waste fuel since the PCM is trying to compensate for a "lean" condition. It will possible cause you to fail emissions testing and it is bad for the environment.

The question is why would you not want to fix this?
The garage I took it to has given me a $900.00 estimate.
They said they had to replace the entire intake manifold. Said they did a "smoke test"?? When isolator bolts were mentioned he said they could not be replaced, the whole unit had to be replaced? Knowing little about this I am quite confused.

Ford service centers have been pretty pricey on this repair, but even they are only charging around $400 for this repair according to other posts. You might want to get a second estimate.

Is there anyway of telling if I go through with the TSB mentioned above for the 171 code (isolator bolts), that the intake manifold itself would still need to be replace as a local mechanic suggested?

Whether the intake manifold "needs" to be replaced or not is dependent on who you listen to/believe.

The 1999 - ??? models had a two-piece plastic upper manifold. (The plastic "upper" sits on a plastic "spacer"). You have to remove the upper plastic piece to see the second piece that is clipped in place inside. As the original design isolator bolt (black) seals shrank due to oil exposure, this whole area gets a bit loose. Most folks get air leaking inside and therefore codes P0171 and P0174. Some folks also get a noise as this inner piece starts vibrating.

Ford upgraded the isolator bolts with a tougher (green) seal. The upper manifold was upgraded with the two parts fused together ... no longer clipped together.

I know of no way to get around replacing the isolator bolts to get the better (green) seals.

But the jury is still out on replacing the "upper". Some folks have had success just reusing the original two-piece affair, as is, as they replaced the bolts. Some of us reused the original two pieces but have added daubs of RTV to help suppress the vibration of the inner piece.

And, of course, some bought the new upgraded part. I don't know how much this thing costs, but it may be pricey.

The isolator bolts are 8 x $7 = (approx) $60 at most dealers.

My 2000 Windstar had the upper intake manifold with separate baffle. When replacing the isolator bolts, I used the orignal manifold; no problems.

Unless the manifold is cracked or otherwise damaged, I don't see a valid reason for replacing it.

I looked up the upper intake manifold at Millennium Ford of Seattle's website.
Same part for '99-02, List price $151.75, Their internet price $109.26

A link to their website http://www.trademotion.com/partlocator/index.cfm?siteid=214072

Look under mechanical parts, fuel system

Sorry. For some reason I assumed you were planning to do the repair yourself. In this case parts could be purchsed for under $100. (Not including parts of the plenum itself).

I have heard of some people getting Ford to chip in for some of the repair. I suppose it all depends on how well you state the argument to them. Go in armed with knowledge.

I wouldn't replace the intake cover, either, unless it was damaged, and I doubt it is. I did this same repair on my 2000 Windstar and used the existing intake cover...no problems. I also found all the parts I needed on eBay. I did a search for "Windstar valve cover" and found a kit with all of the needed parts for $89. The listing specifically mentioned the 171 and 174 error codes.

I can't recommend http://leckemby.net/windstar/windstar01.html enough. I am NOT a mechanic by any stretch of the imagination. I do routine maintenance. The most I had ever done was a fuel pump and master cylinder on a Subaru. But I followed the steps on this website and had no problems at all. It took me about twice as long as the author (about 5 hours) but it wasn't difficult, just time-consuming. Good luck!

Thank you to all that responded to my questions. It was very helpful and lead me to the right person for the repair.
Not feeling comfortable doing the repair myself I took the van to the shop where they gave me a 900.00 estimate! After more questions on this site and more excellant information I checked a Chevy dealer that gave me a 525.00 estimate, a Ford dealer who gave a 475.00 estimate, and finally a 20 yr mechanic who performed the work on the side for 250.00!
Thank you again,
John

:banghead: Ineed help!! can anyone tell explain the process of replacing my EGR valve. Or know a good site I can go to to help me do it myself. I own a 2001 Windstar and it failed emissions. They said it was the oxygen sensor or the EGR valve. Please help!!!

Thanks
Jason