P1517 Chugging engine w/ power loss

Hi!

This forum has really proved a life-saver over the past several years! I appreciate all the time and effort expended to help fellow Windstar owners. I'm currently having a major problem with power loss in my '96. I performed the EGR port cleaning and lower intake gasket replacement a couple of years ago, when it was throwing the classic "misfire on #4 code" and it ran like new for quite some time. I replaced a bad coil pack about 5 months ago and went ahead and did the plugs and wires too. (I had a hard time finding the right double-platinums) Anyway, over the past three months I've been experiencing a gradual power loss at highway speeds that has recently translated into a rough idle and very little power even during city driving. I've tested the fuel pressure at the rails and it holds right at 30, increasing to 40 when the vacuum is off the regulator and holding at 35 for five minutes after shutting down. The only code I'm showing is P1517, but the front butterfly is working fine when I rev it up past 3K rpm. I currently have the upper intake off and none of the EGR ports are plugged - just a little carbon in a few of them, which I cleaned out. Last week I tried removing the EGR vacuum, plugged it and drove around with no change in its behavior. I'm somewhat at a loss as to which direction to head with this thing. (haven't considered the scrap yard yet!) Any suggestions would be most appreciated.

Are you sure the butterfly rail isn't broken internally, as in not actually working even though the actuator is moving it?

The fuel filter would be on my short list. Then cleaning the MAF and IAT sensors.

After that the crankshaft sensor and then the camshaft sensor. These sensors can give problems but be low-level enough not to send codes.

Fuel Filter location, in the picture, the left hand connection is easy....."duck bill" clip. Use a NEW clip on the new filter.
Left hand connection, you need a disconnect tool, available at many auto part stores.
It is a plastic sleeve that slides up inside the chrome connector and releases the clips inside......push it up inside as far as you can.
http://rides.webshots.com/photo/1291091598011220610AirlKU


Camshaft Position Sensor (CPS) location.
ONLY remove the 2 small bolts on the TOP of the sensor,,and the electrical connection.
A easy DIY job
http://rides.webshots.com/photo/2804003860011220610IkRBFJ

Mass Airflow Sensor (MAF) detail, the next picture show a bit more detail.
Spray a NON-RESIDUE ELECTRONIC cleaner into the hole facing you, letting it run out the hole at the other end of the cross bar.
You what to hold the MAF assembly so that the hole that faces you is slightly higher....with the cross bar slope slightly downhill.....with the hole at the opposite end, lower....so that the fluid will run through, flusing dirt out with it.
http://rides.webshots.com/photo/1350023782011220610bXQOkA

Air Intake Temperature Sensor, clean with the same non-residue electronic cleaner as for the MAF
http://rides.webshots.com/photo/1350063274011220610OBlGGb

For the Idle Air Control (IAC) use something like WD-40 or SeaFoam to flush out any dirt.

IMRC detail for the '96
http://rides.webshots.com/photo/2818039750011220610NJerWA

Thanks guys for the suggestions. I failed to mention in my original post that I had just changed the fuel filter less than a month ago trying to problem-solve from simple to complex. I've found myself, in the past, assuming the worst so I've had to learn to slow down and think through solutions sequentially. After I changed it, and noticed no improvement, I bought a fuel pressure gauge to confirm I was getting adequate pressure. I think I will go and disconnect the rail and check that all the injectors are clean while I have it torn down and also confirm that I don't have a linkage or vacuum problem with the front butterfly. A guy at work mentioned that loss of power can point to a camshaft problem. Is there a way to check the sensor or is it better to just go ahead and replace it? Also, I noticed in another thread that if you remove the vacuum line from the EGR to check that system, you should get a code. I've done this twice now and not noticed anything - should I be concerned and possibly suspect the DPFE? Thanks again!
~Mark

....vacuum line from the EGR to check that system, you should get a code. I've done this twice now and not noticed anything - should I be concerned and possibly suspect the DPFE? Thanks again!
~Mark

The fact that you did this (disconnect and plug the control line to the EGR) ... and got no performance change is good = the EGR system is not a problem. The fact that you got no code is a problem ... but a small one, I wouldn't worry about it now.

Continue with the rest of the punch-list. Don't overlook the crankshaft sensor.

I tried to get a good picture of the crankshaft position sensor......but the location is tough....and I did not get a good picture at all.
As far as the Camshaft Position Sensor, if you look down that route, I would just replace.
It is easy to do.

I will add my favorite, a can of Berryman's B-12 Chemtool to the fuel tank.
This is what seems to work the best, for cleaning the fuel injectors, out of the many cleaners that I have tried.

Well, I got it back together this evening after going through the entire list of potential troubles: Cleaned the MAF and IAC and temp sensors and replaced the cam and crank position sensors. I've just had it around town and noticed that it is idling better, but still has no power. Have to pretty much floor it to get it to take off at a stop sign. It backfired a couple times going up a gradual hill - something it hasn't done until now. Checked the codes when we got home and am showing P1517 and P0153 Pd. I see that this is an upstream O2 sensor but what is the Pd? I fixed the vacuum line going to the front butterfly valve so I'm not sure if the first code is a hold over - my little reader won't let me erase just one code. Could a defective O2 sensor cause this much lack of power or should I be suspecting something more sinister?

Thanks again!

Dang! Sorry that you're having such grief.

I wonder what would happen, performance wise, if you disconnected and plugged the vacuum lines going to the IMRC actuators?? .... to see if there is a hugh internal vacuum leak on a diaphragm.

I also wonder if that ignition pack is failing? Was it a new one? They are only warrantied for a year, I have noticed.

Yeah, we all know what a let-down it is when you throw you best effort into something only to receive a "kick in the chops". But not to despair because there is a solution. I had thought about the coil pack the other day when the air intake was off, but didn't check it while being so intent on doing all the other items on my punch list. I think I will run through that check again because I've seen too many times on this forum where somebody has replaced a part and later found it to be defective. I'll keep everybody posted on the progress - will be borrowing a compression tester tomorrow to rule out something major. Thanks for the advice and encouragement!

I was having the exact same issues with my Windstar. After going through almost everything you did, I ran a compression test to find out that cylinder #6 had almost no compression. I hope yours turns out better.