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2001 Windstar Rough Idle / Misfire

04-23-2011, 04:51 PM
My fiance had an '01 Windstar that we have been fighting with for the past year or so. It started off with a check engine light, but it seemed to run ok for the most part.

The local auto parts store read the codes and basically told me it was either an EGR valve issue, or an O2 sensor. However, they could not tell me which O2 sensor it could be. I spent the end of last Fall replacing all 4 of the O2 sensors, but the check engine light remained. With a shortage of warm weather and money, we held off doing anything else because for the most part it ran ok.

Fast forward to today. When she went to leave work this morning it had a whole new set of problems. Very rough idle, backfiring, and other noises coming from the engine. I read the codes in the vehicle and had a cylinder 1 misfire, 2 lean codes, and an EGR valve code. Since we had a lovely day outside I started back in where I left off last Fall.

I replaced the EGR valve, that didn't seem to do much except get rid of the backfiring. I then replaced all the of the cheap Champion spark plugs with new Autolite double platinum ones. The old ones were pretty corroded. I also replaced the spark plug wires with a new set of Autolite branded ones. While it seems to run better now while driving down the road, it still is randomly sputtering and almost stalling out while at idle sitting in park. When I put it into gear, the vehicle kind of lurches as I let off the brakes in both drive and reverse.

I called a friend who is a GM mechanic and he suggested that possibly the fuel pump was failing or I had a bad fuel filter. I bought a new Purolator fuel filter and installed it. With the old filter off, I had her turn the key to run to see how much gas I was getting out of the open line. It instantly sprayed a large amount of gas, so I believe the pump is ok. The old filter was pretty plugged and I could hardly blow any air through it. I can always rent a fuel pressure gauge if need be.

Unfortunately it is still running horribly. I took it for a 15 minute drive, trying to see if I could get any error codes, but no such luck. About 20 minutes after my fiance left to head home, she called to say the check engine light is back on now, so I'll have to read the codes later tonight or tomorrow.

Does anyone have any suggestions as to where to look next? I almost want to say I can possibly hear a vacuum leak, but not 100% sure. It has always sounded that way from day 1, but now I am starting to wonder. Any help or ideas would be greatly appreciated! Thanks for reading!

04-23-2011, 05:14 PM
Mine is a 98 and there was a change made after 1999, however this may help you.

Check the 2 IMRC bellows on the left side of engine behind alternator.

Two things to look for there

1. leaking vaccum on bellow (Remove vaccum line hold the bellow line opening with finger and try to move the butterfly - you will feel resistance if bellow is good and no resistance if there is a leak) and
2. the plastic bushing with link which connect the IMRC bellows to the butterfly.

If this things above is fine than it can be the blocked EGR ports under the Intake manifold.

Thank you.

04-23-2011, 05:14 PM
The autozone person who said it was oxygen sensors or EGR valve was wrong......almost never is the misfire problem caused by 1 of those items.

One thing that is common is clogged EGR ports.
To determine if a misfire is caused by a EGR issue (EGR valve itself rarely fails on the windstar) do the following TEMPORARY test.
Remove and plug the small vaccum line that goes to the top of the EGR valve.
Drive the vehicle........does the problem go away?......
If the problem goes away, then the problem is EGR related, with the EGR ports a likely cause......or the DPFE which senses EGR flow.
If the problem does not go away, then the problem is NOT caused by the EGR system.
Do NOT forget to reconnect the vaccum line to the EGR valve.
This test should cause the CEL to come on and set a code for lack of EGR flow.......because you have disabled the EGR valve from opening at all.

Vaccum leaks are a VERY common cause of problems on the windstar.
Check all the vaccum lines that you can find.....including the one going to the PCV valve.
The upper intake bolts mentioned in the TSB post at the top of the windstar room mention that the bolts that hold the upper intake manifold (black) to the lower intake manifold (alluminum) should have green bushings on them.
To see them, you have to remove the top cover part of the upper intake manifold.

Another very common cause of the problem that you are having is a defective coil pack.
If you have replaced the spark plug wires, then you know where it is.
The coil pack contains 3 coils encased in epoxy.
The epoxy develops cracks through which the high voltage arcs.

04-26-2011, 12:40 AM
Well today we found that part of the problem was a vacuum leak on the back of the motor. One of the lines came loose. At first we thought the problem was solved when the van drove great. At least for a little bit. Then it decided to start stalling out randomly. The check engine light came back on and I had a misfire on cyl 1 again, and and EGR code. I checked the TSB at the top of the forums as suggested, so this prompted me to remove the intake. Sure enough, the bolts and gaskets in there are the stock ones. I checked the local auto parts stores and they all carry a kit (Valve cover, gaskets, bolts, pcv, fuel pressure sensor, etc...) for $98 to fix the TSB. Unfortunately the closest store with one in stock was an hour away. So for the time being I have it torn down and I ordered one and will be picking it up in the morning. I'll post my results later. Thanks for the help!

04-26-2011, 02:43 PM
I'd also clean out the EGR ports while you're in there. I had very similar issues (check engine light, cyl 5 misfire) which was cleared up when I cleaned the mostly blocked EGR ports.

04-27-2011, 08:22 PM
Ok so I got the kit the other night and did the TSB posted in the forums. It seemed to do the trick and the van was running great for less than a day. It then started having hesitation while driving down the road, but not at idle or park. Then today it started acting like it was previously. So tonight I ripped the entire top of the motor off, including the actual aluminum intake. I'm having it professionally cleaned tomorrow morning and I'm picking up a gasket set. Before I put it all back together this time, is there anything else I need to look at while I have it torn down? This is getting old and I'm tired of wasting time and money on it! Hehe... Thanks!

04-28-2011, 05:39 PM
Ok as a final follow up to this nightmare, I have the van running perfectly now. After pulling the aluminum intake off and having it all cleaned very well, I put everything back together. I did find a small coolant leak on the old intake gasket, so it was worth tearing it all down and getting it done right. In the process, the DPFE broke, so that got replaced along with the EGR valve, thermostat, all plugs and wires, front valve cover, upper intake gaskets, & front vacuum lines.

However, once I got it all back together it still was running horribly. I discovered that while my EGR error code was gone, I was now still getting a cylinder 1 misfire code and the engine light was flashing. This turned out to be a bad coil pack that was only affecting cylinder 1. Once that was swapped out, it finally was purring like a kitten and had tons of power!

I do have one last question though if anyone can point me in the right direction. During my test drive I noticed that the heat was only blowing out of the defrost vents by the windshield. No matter where I set the switch, it will not change the output vents. Is it possible I loosed a vacuum line under the hood that controls this or do I need to look elsewhere? Thanks for all the earlier tips!

04-28-2011, 06:17 PM
I actually just found this in another post.

"As a side note, where the air goes inside the van, Defrost, Vent or Floor is driven by vaccum from the intake manifold.
With NO vaccum to the deflectors, all the air will go to the defrost position."

So I will give that a shot.

04-28-2011, 06:40 PM
It sounds exactly like a disconnected vaccum line.....considering all the work that you have done.

When the lower intake (alluminum part) is removed, replacing the motor oil and filter is MANDITORY as there is no way to do that without getting coolant into the oil.
No matter how much you work at draining the coolant, there will still be some up there that will drain down into the crankcase.

One thing that is good to replace when you have the upper intake manifold off is the crossover pipe for the coolant.

Stalling........when you have your foot off of the accellerator is often caused by a sticking Idle Air Control Valve (IAC)......removal and spraying it out with something like Seafoam Deep Creep or even WD-40 would be the first thing that I would try for that.

Installing a new thermostat while you were right there was a very good idea.

Hopefully, your windstar will give you no problems for quite some you have given it LOTS of TLC.

04-29-2011, 06:48 AM
Thanks for the tips. I did a complete oil/filter change before firing it back up. Luckily it was due for one anyways. I did not replace the coolant tube though. It did get a new o-ring seal, and it was in very good shape, so I'm not too worried about that particular part failing anytime soon. As for the IAC valve, I already had that inspected previously and it is functioning correctly. Once I can get back to it later today, I'll fix the vacuum line for the heater and it should be ready for a lot more miles I hope!

06-10-2011, 06:50 AM
Dear All members,
I have 2000 windstar. Had no problems till last years. A few days back driving after 250 KM in hot day it started missing failed to accelerate CEL on for 20 KM. Then drove well for an othe 100 KM. Ford dealer changed feul filter then feul pump a little improvement but not complete. At night when cold, performance is excellent. Yesterday stalled at red light. Then satarted, moved a little but stalled again. After two to three times start and stall it became great but CEL on. Dealer told me it is IAC valve, new not avalilbe so cleaned with WD-40. I noticed that the rpm fall to 550-600 from 750 for 1-2 seconds when I start A/C or put the winny in D mode. Is the fall in the RPM is normalz?
Best regards

06-10-2011, 07:23 PM
Dear All members,
I have 2000 windstar. Had no problems till last years. A few days back driving after 250 KM in hot day it started missing failed to accelerate CEL on for 20 KM. Then drove well for an othe 100 KM. Ford dealer changed feul filter then feul pump a little improvement but not complete. At night when cold, performance is excellent. Yesterday stalled at red light. Then satarted, moved a little but stalled again. After two to three times start and stall it became great but CEL on. Dealer told me it is IAC valve, new not avalilbe so cleaned with WD-40. I noticed that the rpm fall to 550-600 from 750 for 1-2 seconds when I start A/C or put the winny in D mode. Is the fall in the RPM is normalz?
Best regards

Best thing would be to scan it first and see why is the CEL on.

Inspect the coil pack (at the back of the engine) and see if it has any cracks on the back of it (you will have to remove it first) if it does, means it is arching to ground causing the problems you had.

Do you feel your windstar shaking when you stop at a street light?. That could also indicate bad spark plugs and spark plug wires; if those have not been serviced in a long time it would be a good idea to replace them.



06-11-2011, 04:12 PM
Dear Olopezm,
Thanks for kind advice. All this happened three days back. In fact I do not remember cauz it happened only twice or thrice and I could drive to the dealer. But most probably it did not shake. I told you that the dealer suggested me to change the Idle Air Controle which was not available. I cleaned it with WD-40. I was driving with on CEL for two days with only occasional jerks (3-4 Per day). Dealer was waiting for IAC to reset the computor. Today strangly the CEL light autmatcally was off. I changed plugs 12000 KM or 12 months back and I will change them in next week. I have changed Air filter about one month back, the gear oil and filter today (after 12 month). I got scaned the gear it was OK. I want to know why it is jerking for 2- 4 time in a day while at start, during accelerating and during constant speed.
Best regards

06-12-2011, 09:04 PM
You're very welcome my friend!

If the dealer told you the problem was the IAC then that would be the first thing to check, you say you already ordered it; when the valve is dirty can stick and not propperly open or close according to the PCM commands. Cleaning it would get rid of all the dirt and make it move freely again. The light turned off because (in case CEL was pointing towards a IAC problem) the IAC works normally again and the air is being regulated properly.

IT IS RECOMMENDED that after you make any repairs in the engine compartment you should disconnect the negative battery terminal for 30 minutes in order for the PCM to erase the previous "performance" values and re-learn them again with the new components.

The plugs still have a low mileage, if they are in a good condition when you take them out (meaning they don't have any oil or carbon deposits, broken electrodes, etc.) you can just make sure they are correctly gapped and re-install them again. If you still want to replace them I've read in the forum that is best to use double platinum spark plugs.



06-12-2011, 09:11 PM
I forgot to ask How long since you last replaced the spark plug wires?

If it's been a long time it would be a good idea to get a new set of wires. You can test them by using a spray bottle, put some water in it and spray along the spark plug wires, if one of them is shorting you should see sparks coming coming out; this test works best when done at night.


06-13-2011, 05:02 PM
Dear Olopezm,
Thanks, I donot know when last time the plug wires were changed. I have one question how often the MAF and IAC Or any other thing should be cleaned? It makes sense because old cars were regularly taken to workshops for "tuning". So as not be stuck in a deserted place. Can I use wd-40 for cleaning throttle body?
Best wishes,

06-13-2011, 06:23 PM
In that case I think it would be a good idea to:

Replace plug wires
Check spark plugs for correct gap

If the problem still does not goes away, then I would clean the throttle body. But the best way to do it is to take it apart from the engine instead of using spray cleaners, You can use some gasoline to clean it with a paint brush (I like to trim the brushes hairs so they are not too soft). The IAC, because it's an electrical part, needs to be cleaned with a electric parts cleaner or throttle body cleaner when available, maybe using some gasoline to clean it might be or not a good idea, just make sure it doesn't gets into the electric motor and you might be fine. The idea is to get rid of all the carbon build up inside these parts.

I don't recommend using WD-40 to clean that type of parts because of it's oil based formulation, if it's not correctly washed off it will tend to collect dust and dirt and you will end up with a sticky compund which will cause more problems in your engine if it goes into the combustion chambers.



06-15-2011, 03:24 PM
Dear Olopezm,
Now the problem is over. I drove about 102 Km in hot weather with smooth drive, except AC problem which I will recheck. I used motorcraft feul injector cleaner. But still I intend to clean The MAF cleaner, throttle body and check Throttle position sensor. After that I will let all u know.
Best regards

06-15-2011, 04:00 PM
I'm glad you seem to have fixed your problem. I guess the next suggestion would have been to clean the injectors (just realized windstars are very delicate with injectors and need periodical cleaning).

Take care!



08-23-2012, 06:18 PM
Dear members
Wiswind, Olopezm, 12Ounce and Tempfixitis are experinced and good advisers. I appriciate them. but read these two posts/ threads. You will also appriciate them and may find some solution. ( (

08-05-2013, 12:04 AM
OK. So I have been reading over these posts, and all of them mention the same thing; codes. My problem is different.

We own a 2001 Windstar built in Canada, and, so you know, the check engine light has been on in the vehicle since we bought it FOUR YEARS AGO.

The van has been a trooper for most of that time, only giving us mild problems which have always been fixed immediatly.

But thie problem we are having now is baffling me, because there are NO codes.

The problem is simple. When idling in park, the engine runs good. But once driving it, when stopped at a stop light or whatever, the ldle lurches up and down. But the van never comes close to stalling, nor does it seem to be running “rough”.

When this problem started, there were codes. I needed to replace the IAC and the TPS, which have now both been fixed, and the computer has been reset in case you are wondering.

I have replaced the PCV valve and the hoses that run to it, as the valve itself was nasty . . . probably factory.

I am replacing the DPFE, though there is no code to say that I need to.

i DID have the 101 and 104 codes before I replaced the IAC, but once it was replaced all codes went away.

So . . . what is my problem here? What am I missing? If there were codes or whatever, I would understand. But even with the check engine light on, there are now no codes, so whats wrong here?

The van has also had the following in the last year. New e3 spark plugs, new plug wires, new coil pack (the old one was cracked so it had to be replaced) and a new output shaft sensor on the trans. Oh, also the abs sensor connected to the master cylinder and the mass air flow sensor. Seems like I am pretty much all sensored out here.

I have yet to check the vacuum lines, as the posts above tell me to do, but could it be that simple? I have read elsewhere that the intake manifold gaskets and egr system could be blocked up, but again, there are NO codes. I just dont want to lose this thing, as it has been very reliable and is actually a beautiful peice of machinery. Its the SEL model.

I read somewhere that moisture getting into the PCM (ECM) could also cause the problem, but woulsnt THAT cause a code?

I am thouroughly confused here and need to figurew it out before my bipolar wife decides to . . .well . . you can fill in the blanks there . . lol.

Any advice or knowledge would be greatly appreciated.

Scott in Cleveland, ohio

08-05-2013, 07:44 PM
Hi Scott,

Seems like you've done a lot. Idle surging would indicate either a problem with fuel or a vacuum leak.

Check for vacuum leaks first; check between the upper and lower intake manifolds to see if there is any oil seepage between both. The isolator bolts (if not done already) cause a vacuum leak (although not too serious but still worth to check) which could be causing your problem.

It would be easier if you have access to a live data capable scanner.

To check fuel pressure you'll need a fuel pressure gauge tester available for rent at most autoparts stores (you'll get your money back when you return it). Pressure should be 32-45 PSI with Key ON/Engine Off and should drop about 10 PSI after starting the engine (32 PSI is the minimum for the engine to run properly). Remove the vacuum line on top of the fuel pressure regulator and PSI should go back to the same reading as KOEO. If you remove that line and see any fuel coming out of it, that's your problem and need to replace the regulator.

EDIT. Before you replace the DPFE sensor, you could try disconnecting it to see if it makes any difference. That will disable the EGR system. The all plastic (black) sensors are an improved design that doesn't fails that often; it's the metallic ones that are problematic.


08-05-2013, 09:15 PM
Thanks for the response Oscar. Funny you should mention the fuel system because that was the pre-curser to all the problems we have been having.

I forgot to mention that during the winter, we had to replace the fuel pump and all the filters (in tank and out) which created yet ANOTHER problem of the fuel gauge not reading right in the dash (a story for another day . . .lol).

This is what led to the difficulties I am having now.

So, I did what you suggested with the DPFE, unhooked it and it made no difference, but it was metal, so I just replaced it anyway so it doesnt go bad on me later.

But I DID notice something interesting today. I started wondering if I had gotten a faulty TPS, so I unhooked it and it also made no difference. But check THIS out. Just for the sake of argument, I decided to unplug the IAC and WALLAH!!!! The rough idle and lurching went away.

Now before you ask me, i did replace the IAC. TWICE in fact. The first one I got from the part store was defective and was sucking air like crazy. It made a loud whistling noise when I revved the gas, and it wouldnt stay running.

So I took it back to the part store and they replaced it, and this one is actually functional ( I guess). Its just funny that it quit running rough when I unhooked it.

The idle kicked down tremendously and the lurching stopped. I took it around the block and it ran damn near flawlessly.

BUT once the engine got cold and we had to drive it again, it wouldnt stay running, I assume because the engine was cold and the IAC wasnt controlling the air mixture, so I hooked it back up.

I am going to check those pesky vacuum lines tomorrow and I am hoping thats all it is, but it worst comes to worst, I am going to do the entire manifold kit (gaskets, bolts, cleaning of the ports, etc to hopefully gety it to stop.

Out of curiousity, is this thing supposed to get like 10 miles to the gallon? Because on its best day thats about all it gets. The engine does have almost 200,000 miles, but its very clean and WAS running great, just never got good gas mileage.

Oh, one last thing, where is the Fuel Pressure Regulator located on this vehicle? I am an Oldsmobile man myself, so Im pretty familiar with GM's setups, but this ford has me going nuts. I just figured out where the damn egr valve was, and ive had this thing four years . . . .lol.

08-05-2013, 11:24 PM
I has been my experience that as these engines with the mechanical throttle body and electric IAC ... that as things wear, the "factory setting" on the the throttle plate stop is no longer correct ... especially as we change other control items on the drivetrain. Of course, the screw-stop that is given to us on the throttle body is not easily adjustable ... and I usually take the throttle body to the work bench and do some "severe surgery" to replace the original screw with a regular hex-head screw (of the same metric threads ... often M5-.8) ... and I add a nut as a lock. Now there is some adjustability ....!

After resetting the throttle plate stop-position to suit, I am able to get better idle for all conditions.

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