03 Windstar chugging on hills

Hello all,

2003 Windstar 3.8
135,000 miles
Did TSB/Isolator bolts approx 30,000 miles ago after P0171/174 codes, they never came back
Had been running rough/stalling immediately after starting a few weeks ago, CEL came on - lean banks 1 & 2 (wife didn’t get exact codes from Advance)

I replaced:

fuel filter
plugs
wires
clean MAF
cleaned IACV
can of Berryman’s in tank
cleared codes
Now starts and idles great, but misses/chugs on hills under acceleration (didn’t really notice that it did that prior to plug change --???) this is NOT tranny slipping but engine stumbling


Checked fuel pressure:

32 PSI at idle, goes to about 35 when I rev it up, but it corrects back to 32 PSI around 3000 rpm
Unplugging fuel pressure regulator, it rises to 40 PSI (no fuel in vacuum line)
Pinching return line, pressure rises to approx 50 PSI
Holds pressure after 5 minutes per specs in Chilton manual
Sprayed carb cleaner around intake/hoses while running, no difference
Van is at mechanic now, still not throwing a code except once, a random misfire (CEL light flashing). Starting/running great at idle but missing/hesitating on highway under load. If you punch it, it drops a gear and goes reasonably OK He tested a replacement EGR controller (not sure exact term, but it sends the vacuum signal to EGR) with no difference.

Some questions in my mind:

Is fuel pressure OK? Chilton book says 28-45 PSI, so seems OK, if marginal? Seems to me the fuel pump is not suspect since pinching the return allows it to pressure up to 50 PSI?
Ignition? Coil pack? Seems this should throw a code.
Does the lack of a code indicate anything (fuel side rather than ignition?)

Any help/suggestions would be so appreciated – the wife wants her van back!!!

Thanks!!

What type plugs did you use..?? If you used auto lights dp.. make sure they are App 105..

i'll have to check to be sure - got them from Advance auto - brand is slipping me at the moment - but they were listed under that model/year

Its funny the spark plugs are funny on these things.. Double platinum type work the best but Most run the Motorcraft or Auto light.. I got the auto light 765.. Mine had a bump shudder over a year. Switch out to the APP 105 and problem solved.. Same brand spark plug.. Just the threads were shorter on the 765.. 105 has the full thread.

I have heard the same thing before about the plugs clearing the problem up, but also know from experience with my 01 Windstar that I had similar condition (P0401 misfire and studdering under light load going uphill and OK when you punch it) to what you describing and for me it was the DPFE sensor was stuck at one voltage. Since the voltage wasn't changing the amount of exhaust recirc was not changing, but as you accellerate, the ration of exhaust to oxygen was changing, so that in some conditions everything was fine, but in other conditions, there was not enough oxygen so it would run rough. If you are interested more in this, search this forumn for DPFE as I have explained it a couple of times.

Thanks, I'll look into the DPFE.

Plugs are NGK TR55 V POWER. Anyone use these??? Thanks!!!

... could be the EGR jets have plugged back up.

Sometimes cleaning won't work on the IAC valve ... has to be replaced.

did this problem get solved? I'd be betting on the plugs as well.

FWIW, I think everyone should just buy plugs from the dealer. I've always done that on my van and never had any probs.

P

I have used both Motorcraft and Autolite double plats with success.
I have read about problems with the Bosch multiprong plugs (+2 and +4) in the windstar, but have not read anything about NGK.
I do prefer to stick with the Motorcraft or Autolite double plats.....as this is what the vehicle design calls for.

The EGR "controller" that your mechanic tested would most likely be the DPFE.....which is what measures the EGR flow into the intake.
It is a common failure item.
One can do a temporary test......which will light the CEL for lack of EGR flow....as you will be disabling the EGR flow.
What you do is remove and plug the vaccum line that goes to the top of the EGR valve.
Go for a drive.......if the vehicle still "chugs" on the hills.....then the DPFE EGR is not the problem.
If the vehilce does not chug on the hills.......then the EGR IS the problem....and the first thing that I would try is the DPFE.
Reconnect the vaccum line to the EGR valve......as this should ONLY be done as a temporary test.
The EGR valve is pretty reliable on the windstar......the DPFE is a known common cause for EGR problems.

I have an '01 Windstar, 114,000 miles

I am having a similar problem, cylinder one misfire (P0301) when under increased load at around 1900 rpm. Condition worse if the AC on, which of course is more load If you punch the condition goes away.

Did the isolator bolt fix a few months ago and removed the too lean condition problem. Cleaned the EGR ports when I was there and also changed the plugs on cylinder 4, 5 and 6 (plugs looked in pretty bad shape). I have also changed the IAC, DPFE, and EGR valve. I think the vacuum is in good shape. I have also run Seafoam and Berryman through the tank and also sucked it in through the brake vaccuum line. Should be pretty carbon free at this point.

I guess I need to change those plugs on the backside near the firewall to eliminate.

BTW - I took it over to a small garage that will do simple things with parts you supply and they refused to put in the plugs because its too hard to reach. Something about needing 10' arms. I probably should of tried harder when I had the wiper motor, cowling, etc. off.

I am going to put the van up on ramps and see if I can reach them from the bottom this weekend.

any other thoughts?

Obviously not an experience Winny mechanic. The rear plugs can be reached two ways: 1) reach up from unerneath and change them blind while lying on your back or 2) (the way I prefer) pull the wiper cowel off and you have EASY access to thr rear three and you can see what you are doing!

The cowel takes about 10 to 15 minutes to remove. I have had the cowel off so many times that last time I got smarter and set up my drill to take out all the 8mm bolts in the cowel and cut the time in half. Good luck.

Have you tested the new DPFE sensor? I would, because the aftermarket one I bought only lasted 6 months. Exact same result for a friend. The brand we bought was Nehoff at Lordco for $50 (I have a bit of a discount). I went to Ford this time and paid $100. Hopefully this one will last.

Andrew - Thanks, I will take the cowling off. Could you reach them straight away or did you need a flex/swivel extension?

I will also check the EGR sensor

Straight with an extension, but no swivel required if my memory is correct. Make sure to use a rubber lined spark plug socket or you might crack them when installing them.

I use the "lay on your back" method to change the back three with a 3" extension and a rubber lined socket. The hardest one is closest to the passenger's side.

I am dealing with this issue on my '99 so I will be watching this thread. Good luck to you. Andrew was a big help.

I do mine from under the vehicle.....
Just drive the front end up on ramps and lay under there.....reach up to them.
Very easy.
I ONLY remove 1 plug wire at a time......and do that plug, then move to the next.
This eliminates the possibility of crossing the plug wires.....connecting them to the wrong plugs.

Cylinder #1 is on the back side, drivers side.

Done - 20 miles of driving, no more missing. The plug in cylinder 1 was in definite bad shape. Went from underneath. A challenge to the flexibility for this FOG.

Thanks to all, great site.