'98 3.8L with P0171,074,1537,1538,0304

[Trons]

Greetings,

First, Let me say thanks to everybody who has posted on these problems in the past, especially the 0171. After reading the posts I decided to do the lower and upper intake gaskets. While doing those, I've found that my front IMRC is bad (Guessing diaphram).

I determined this while my manifold was sitting on my workbench by plugging the vacuume line hole with my finger and moving the butterfly valves. My back side will only move about 1/3 the way then I can't move them until i remove my finger from the vacuume line hookup. The front, it doesn't matter.

My questions are these:

a) Is this an accurate test or would they be different for some reason?

b) I thought I had read on this forum a place to get these for $150 (there abouts) which is a lot better then paying the $250 from the dealer. If I can find them for $150, I'll jst replace both of them while I have the thing torn apart so I'm not doing this again in 6 months.

c) what is the best way to clean the intake manifold (lower) gasket off the head without gunk getting down the ports to the valves...(short of being really, really, really carefull).

d) Does anybody want to buy a Ford windstar as a project vehicle, I think I know where there's on cheap....

Thanks for all the help, both in the past and future.

Trons.
"If you want something done right..."

[12Ounce]

a) You're pretty much on track. Do you have one of those plastic hand vacuum pumps? AutoZone has them for about $20 bucks. They are awfully handy for this kind of sleuthing.

c) First, stuff some wadded shop towels into each hole you want to prevent something falling into. I have a spray can of gasket remover (by GM, I believe) that really softens up any gasket ... making it easy to remove.

d) Thanks for the offer. But I already have mine. About to drive it on a little trip ... I think. LOL.

[egstasea]

trons, I also have a 98 and have fixed the same codes over the past month with the exception of 304.

IMRC vacuum accuators - both 1538 and 1537 will show up with one bad diaphram. Pull and plug the hose on one, start and rev the engine and check for proper operation on the other. Repeat process for other. $10 says when you have the front one plugged the back one will operate, but not vice versa. That means the front one is bad. The part is available at fivestarford.com for the prices you indicated. Call and ask for the internet parts guy. Also buy the $5 clip/bushing. I found it real easy to change the front one with the alternator off.

171-174 - on a pre 99 these usually just mean a vacuum leak, or dirty MAF. What the computer is telling you is it can reconcile the the reading in the o2 sensors with the amount of air coming through the MAF. This is probably because air is getting in somewhere after the MAF. I would not be suprised if it is related to the vacuum accuator above. The 98 does not have the 2 part intake and the manifold leaks assoiated with the newer models.
I would fix the imrc vaccum accuator first, and see if you get rid of the 171 and 174 codes.

That being said if you still have 304, you are going to pull the intake manifold any way to clean the egr ports, at this time you might as well put in the 6 gaskets.

As an aside, I had to chase down 2 other vaccum leaks on mine. The elbow off of the top of the intake developed a leak, and the new pcv valve I put in kept popping out.

[Trons]

Thanks for all the help. I think I forgot to mention a few important points...

a) I'm already half way through the job (Have both upper and lower intake off and waiting for parts ordered and time to do it)

b) I'm not really a mechanic, I don't even really play one on TV. I work on my '84 toyota 4x4, but if I screw that up, my brother-in-law is an expert on them so I'm not to worried.

These new fangled (I'm not really from KY, but I'm trying to fit in ) engines with all these wires and sensors and such are not as much fun as a simple 4banger.

I've already (in the past) replaced the PCV and cleaned my MAF. I'm not real impressed with the windstar as yet. It only has 90k miles on it and i'm having more problems then I've had with any vehicle in the past...of course, that could be because it's much harder to work on....

I'm really interested in finding that IMRC for a cheaper price then the dealer has it for.

Trons
famous last words: "hey ya'll, watch this..."

[wiswind]

If your defective IMRC is also leaking air.....that is a vaccum leak.

I also had the elbow on the top of my upper manifold develop a leak.....it goes to the PCV valve.....and a few other places that are tapped into the line.

Buy a motorcraft PCV valve....others may permit too much flow.....and excessive oil in the intake....resulting in carbon buildup in the combustion chamber.
Make sure that it seats well into the gromet.....or that will be a vaccum leak. You can buy a new gromet if the old one is worn.

The air that flows into the crankcase, through the oil breather....that is mounted on the opposite valve cover....to replace the air that is drawn out through the PCV valve.....is measured air that has come through the MAF sensor....which is why air leaking in from elsewhere is a problem....

Clean your MAF sensor....I listed step by step instructions in a couple of other threads.....a search on MAF should lead you to them....use non-residue electronic cleaner....

Also.....I would spray some carb. cleaner inside the cup that is over the spray end of each fuel injector.....
I spent a few months tracking down a slight miss...that ended up being crud in there...even with use of fuel system cleaners.....

These are things that are good to do...while you have it all apart .....so it does not get any easier to do than it is now.

DPFE is also a high failure item on these.....That is the sensor that measures EGR flow. So if you get a code for EGR flow....change the DPFE out....Easy and cheap.

These are a few things to keep in mind....that could end up saving you some serious bucks.

Oh....here's a good one.....The distributor?....It's only partly gone....The sychro gear is still there.....and.....at the top of that sits the CPS (Camshaft Position Sensor).....aka "pickup coil".....
It's right over there near those IMRC units that you are replacing.

[egstasea]

In case you missed my suggestion, call the internet parts guy at fivestarford.com. They are an Arizona Ford dealer, but they are willing to sell motorcraft parts without the 100% markup. My local guys wanted $260 for the imrc, 5 star was $150.

[Trons]

Greetings,

I want to thank everybody who has posted a reply on this thread specifically, and about this problem in general. I was able to order the IMRC from 5-star (It came today and the people were great. I now have a place to go other then the idiots at my local ford dealership...thanks again for that one thing alone).

I am about to start putting it back together again. This is where I usually have problems with vehicles. Getting them apart isn't that big of deal. Getting them back together again so they run is . I'm hopeing that all the precautions I took while taking it apart will pay off, ie: keeping all the bolts to a specific piece together and seperated and labled and cleaning everything.

I will be sure to post any problems I have on this forum before trying to fix them myself. Again, everybody has been very helpful and I am extremely gratefull.

Trons
"Hey ya'll, if you thought that was cool, watch this!!!"