codes 0171 and 0174

[bmm95]

I have a 1999 Windstar with 130,000 miles. Check engine light has been on for a couple thousand miles with no change in performance. I relaize I should have addressed the problem right away but my busy lifestyle got ahead of me. Long story short, had the codes read and they were the highly talked about 0171 and 0174 codes. I have seen the posts on the most likely cause being the gasket in the manifold. My questions are, how can you tell if the upgrade has been done since I bought the vehicle used, and what are the long term effects of this problem. If I have to wait a couple more weeks, what damage will I be doing to the vehicle. Thanks for any help or advice anyone can provide.

[DRW1000]

Technically referred to as "port seals". How many miles when you bought it? Sounds like a typical mileage for it to occur. The old and new design of the Isolator bolts -which you will need to replace to correct this defect differ in colour. If someone has done the complete TSB at the dealer one can check the TSB itself. There is a procedure to determine the old and new valve covers. Chances are that if replaced this you probably did the rest (the actual faulty items) Incidently it is the Isolator bolts that cause the problem.

Search for Isolator bolts, and TSB 03-16-1(IIRC?)

[DRW1000]

Damage

Van - cats (so I have been told), fuel economy
Environment - excessive emissions!!!

[Mudsculpter]

You are not doing damage at all. I drove mine for months before I figured out the problem. You won't be able to pass an emmissions inspections if your state requies it though. Yer probably not getting good gas mileage and it may idle rough at times especially in the winter mornings.

The fix

Go to the ford parts desk and get the lower plenum (it is the black plastic tray that sits atop the intake manifold) it comes with all the isolator bolts and new seals too and cost just a little over $100 for all you need in a neat little box. Just remove the old and set the new one down, torque the bolts in the right order and yer in business. Dont forget to check all the vaccuum lines for dryness. (hell, just replace them all while you have it taken apart) you may as well replace all the plugs and wires while you have easy access to them in the back.

What are you sitting here reading this for,.... get to work and fix yer van!

[wiswind]

http://leckemby.net/windstar/windstar01.html

Very detailed information on what you need to do...with pictures......

[Mudsculpter]

Originally Posted by wiswind

http://leckemby.net/windstar/windstar01.html

Very detailed information on what you need to do...with pictures......

Excellent tutorial with the exception of the parts list (along with the vaccuum hose stuff, buy the lower plenum), it has the isolator bolts and isolator bolt seals with the lower plenum and new plenum seals too. Ready to drop in and tighten down. Check with the parts desk just to make certain that it still comes this way. I did mine last year or two ago and no mil light since.

[DRW1000]

The "lower plenum replacement box"?

Is this the lower half of the plenum? If so there is no reason to buy this unless the old one is cracked.

You should replace the port seals and the Isolator bolts. While you are in there you can clean the EGR ports. If your fuel pressure regulator is loose then replace it. You could also replace the upper to lower plenum gasket. I only did because I bought it but I doubt I really needed it. I think the valve cover replacement is unnecessary.

The actual work is time consuming but not very difficult for someone with mechanical abilities.

[Mudsculpter]

Originally Posted by DRW1000

The "lower plenum replacement box"?

Is this the lower half of the plenum? If so there is no reason to buy this unless the old one is cracked.

You should replace the port seals and the Isolator bolts. While you are in there you can clean the EGR ports. If your fuel pressure regulator is loose then replace it. You could also replace the upper to lower plenum gasket. I only did because I bought it but I doubt I really needed it. I think the valve cover replacement is unnecessary.

The actual work is time consuming but not very difficult for someone with mechanical abilities.

What I thought I SAID was That if you buy the lower half of the plenum you get the isolator bolts and seals and gaskets WITH it already seated in their respective holes. For a few dollars more you get the whole lower part of the plenum replaced.

[DRW1000]

I would find it hard to believe that it is only a few dollars more but in any event iirc the throttle body is attached to the lower plenum. does it come with this gasket and does our thread starter really want concern himself with removing the throttle body ? Unless there is something wrong with your old one I would not bother.

[Mudsculpter]

Originally Posted by DRW1000

I would find it hard to believe that it is only a few dollars more but in any event iirc the throttle body is attached to the lower plenum. does it come with this gasket and does our thread starter really want concern himself with removing the throttle body ? Unless there is something wrong with your old one I would not bother.

remove the throttle body? why would you have to do that? Yer going to remove the lower plenum anyway to clean the ports why not replace it if it doesn't cost that much more?

[DRW1000]

REMOVE THE THROTTLE BODY FROM THE OLD PLENUM AND TRANSFER TO THE NEW PLENUM. (IS that clear?)

Isn't the throttle body connected to the lower plenum?? If not then my memory is failing me. If it is then in order to replace the lower plenum then it would be necessary to remove the throttle body from the old plenum and reconnect to the new plenum. If the old plenum is used then these steps are not necessary. Personally I don't see the point but it is up the guy who started the thread.

In any event the original question was how can he tell if the TSB was performed or not prior to him purchasing the vehicle? The colour of the rubber on the Isolator bolts is the clue.
Green = new design,
black = old design.

[Mudsculpter]

Oh right, I stand corrected, It has been awhile since I performed that particuler service.

But by only removing the isolator bolts and seals and reinserting new ones in their place only takes care of half of the problem. You want to remove the plenum entirely and clean the top of the intake manifold and clean the crud out of the ports too. Rreplacing each of the six seals underneath the plenum will complete a rock solid repair.



My point is that while you have all that apart replace it for a few bucks more. I dont know how much easier I can make it for you to understand.

[DRW1000]

It is not a matter of a lack of understanding but rather a difference of opinion. I thought that was understood by you.

I agree that you need to clean the plenum and the top of the lower intake and replace the seals and Isolator bolts. It is also a great time to clean the EGR ports and even replace the spark plugs if they have not been done before. However, all this can be done without removing the throttle body. and perhaps a few vacuum hoses. In order to replace the static lower plenum the throttle body and all vacuum lines need to be removed.

Of all of the posts I have seen here in regards to 171/174 and the isolator bolts I do not believe anyone has ever replaced the plenum itself but I will admit it could be done.

It will add the following:
-Increased cost - or so one would imagine
-More disassembly.

I am not here to argue with you however I am just offering my opinion just as you are. Both solutions will work.

[bruker]

Mudsculpter,

Do you know what the Ford PN is for the lower plenum which contains the bolts and seals?