real head scratcher p171 and p174 codes

[oldfart1969]

Hi all,

Ive been dealing with the dreaded p171&p174 codes on my 2000 windstar.. I found a great reference at http://leckemby.net/windstar/windstar01.html to repair the problem. I followed these instructions step by step and they worked!

codes are gone no more engine light. however my exhaust is now blowing white smoke as if the head gasket is blown. I don't see any of the common gasket tells such as milkshake or bubbles.

My question is this - Could anything I did while removing the intake manifold and replacing the gaskets cause this problem, or is my dear old 3.8 just turning into money-pit? I'm hoping someone is going to tell me a vacuum hose or or bad pcv valve is the root ... Id be petty ticked if I did all that work for nothing

[ctwright]

do a compression check and come back with the results

[olopezm]

Welcome to the forum!

Sorry to bring bad news, but white smoke is usually a sign of coolant leaking into the cylinder and being burnt.. I suppose the white smoke has a sweet smell.

- Did you follow the proper torque specs and procedure to tighten the manifold?
- Has the van being overheated any time?
- Not sure on this one but I've heard/read that if you don't change the coolant at the specified intervals the heads can be blown.

Best regards,

Oscar.

[wiswind]

The 1995 3.8L windstar had major issues with headgaskets blowing.
The other year, not very common.
HOWEVER, the lower intake manifold gaskets can fail.....creating MANY of the exact same symptoms of a blown head gasket.
The lower intake manifold gaskets can leak coolant into the intake passeges.....and is then drawn into the cylinder(s).
The new lower intake manifold gaskets that are out now are improved.......so, should you need to replace them, it is not a failure that is likely to return.

Doing the Leckemby process.....you should have not bothered anything that would have impacted coolant into the motor.
The coolant does NOT go into the upper intake manifold (the black part), it DOES flow throught the lower intake manifold (alluminum part).
If the lower intake manifold is removed, the lower intake manifold gaskets.....the gaskets that go in between the lower intake manifold and the head MUST be replaced.
The upper intake manifold gaskets ARE re-usable.

Maybe the white smoke is just normal exhaust in the recent cold weather that is in New York?......just trying for some wishful. easy, cheap explanation.

There are other leaks possible......the crossover (bypass) tube that passes through the lower intake manifold......I do not know how it is arranged on the 1999 and newer windstar, but the pictures at the Leckemby site should show it clearly.
If that tube passes through any part of the intake passeges.....the part that is under vaccum present in the intake.......then it could be the cause.
On my '96, it was not in the same section....just passed through the lower intake manifold, so the only place that I can think that it would leak would be into the crankcase.....not the intake.

[oldfart1969]

Hey guys,

Thanks for the quick replies! unfortanitly I think you guys are right in the ballpark on this one..... I was just hoping there might have been something I screwed up while replacing the bolts and gaskets on the upper intake. Oh well looks like Ill get to get my hands dirty again. Wiswind- how tuff is it to replace the lower intake Manifold gasket, is it something a weekend warrior like myself could handle and lastly is there anyway for me to varify its the lower intake and not the head?
welp I plan on letting the beast sit for turkey day and Ill get to it over the weekend- let you know how it goes.....

[wiswind]

The lower intake manifold is not real easy.
It is messy, and takes a lot of time.
You need a beam style torque wrench that measures INCH pounds.
I have pictures posted in the pictures that the link in my signature takes you to that covers the lower intake manifold process.
I would also replace the cross over tube that goes through the lower intake manifold.
I have it pictured in the pictures.
It is different on your 2000, but it is there, and I have seen enough posts on it leaking on the 1999 and newer windstar to make me strongly advise you replace it.
I am hoping that someone with a 1999 and newer windstar will comment if this tube can leak into the intake (and be drawn into the cylinders) and show the symptoms you are having.
It is NOT the case for my '96 that is shown in the pictures.

Please note that the pictures and information in my pictures is for the '96, and your 2000 will be different, but similar.
They made a LOT of changes in the 1999 model year.
You will particularly need to use a repair manual for your 2000 model year and follow the torque specifications for your 2000 which could well be different from my '96.

Of course, my advice that the oil MUST be draind and replaced AFTERr the new gasket is in place and everything is back together.....But BEFORE you start the motor for the first time after putting it back together.
The reason is that you WILL get coolant into the crankcase when you lift the lower intake manifold up off the heads.

Also, expect the "quick connect" for the heater hose (if your 2000 has that) to fall apart.
You should buy one to replace it and have it on hand.

Also, use care to avoid getting stuff down into the intake ports in the lower intake manifold and/or into the intake ports in the head.
You can guess where anything that gets into there is going to go when you start up the motor.