2000 windstar stumbling/hesitating

Hello,
I have a 2000 ford windstar that just started stumbling/hesitating when I press on the gas (http://www.2carpros.com/forum/2000-ford-windstar-hesitating-stumbling-vt454681.html) at the 35-40 mph range. It does it at other speeds too but not near as much. It started about a week after I had my fuel filter Changed. I already had the isolator bolt problem fixed about a year ago and that’s fine. The service engine light Has not come on with this new problem. Thanks

Well it seems that I'm not the only one stumped by this,
I posted it here and another board and not one reply.
oh well thanks any ways

First thing that I would think of.....since you don't mention any CEL, would be the fuel filter.....which you changed.
You might try having the fuel pressure checked......the OBDII system does not monitor fuel flow or pressure.
It sounds like it could be a fuel delivery issue.

There's not much information in your post to go by. It really could be many different things. Anything from spark issues, fuel delivery, emissions control, timing, air flow...

Check your air filter, since it's easy.

It's hard to know if the problem is due to changing the fuel filter, or that's just a coincience. You could focus on that for a while. The filter is not that expensive, so you could try a different one to see if that can cure the problem. I don't know if you could temporarily eliminate the filter with a direct connection from the tank to the fuel line, but that would be another way to eliminate the new filter as the cause. However, be careful with that approach as any dirt in the tank that would normally be caught by the filter will clog your injectors and create even bigger problems.

I've had misfire issues due to clogging of the EGR ports, which you can only check by removing the upper intake.

The spark plug wires or a bad coil can cause misfire.

Sometimes the torque converter clutch in the transmission can chatter, which can feel like a misfire or shudder. I know it doesn't help much to have such a wide varying list, so maybe you can learn some more to narrow down the options.

Have you checked your intake manifold runner control? It's located on the passenger side of the engine to the left of the plastic intake manifold. It's an electric device (about the size of two decks of cards) that has two arms that vary the intake manifold runners. They have small plastic clips that hold the arms in place. The plastic they used was crap and they fall out. If this happens, your engine will stumble under light acceleration, but clear if you floor it. (Mine did this and luckily I found someone who told me about it). The replacement parts are available in the "HELP" section of most auto parts stores. I bought mine at rockauto.com, but they can be purchased locally I'm sure. They cost me like $2.

I hope that this fixes your problem. Let me know if you can't find the problem and I'll take a picture of the device.

Mark

I took it to the garage today and should find out tomorrow what it was. I’ll post on here so hopefully it might help others. Thanks for the input and suggestions

Bill

Weird, I'm having the same issue with an '02. I noticed if I floor it in the 35-40 range it has no power/accel and bogs down real hard but if I let off the gas real quick then hit the floor again it takes right off and has tons of power. I was thinking something with the trans like tomj76 said but I can park it and rev it up in the driveway and get what feels like misses. If I floor it in the driveway I can't get it to go ovr 4000 RPM. Very strange - no CEL.

I am having a nearly identical issue - please continue to post what is happening with yours for all our benefit. What was the result of putting it in the shop?

I have changed our fuel filter (last summer), changed the spark plugs, then the O2 sensors, then the throttle position sensor, then cleaned the idle air control valve & the egr valve, then did the intake bolts & valve cover fix, then lastly changed the plug wires. None of these fixed the stumbling/missing issue it has, but like you we get no check engine light. Ours misses under light load as when cruising on the highway at, say, 60-65mph, and at idle, but when we floor it it has all its power & roars off. I'm stumped.

I am having a nearly identical issue - please continue to post what is happening with yours for all our benefit. What was the result of putting it in the shop?

I have changed our fuel filter (last summer), changed the spark plugs, then the O2 sensors, then the throttle position sensor, then cleaned the idle air control valve & the egr valve, then did the intake bolts & valve cover fix, then lastly changed the plug wires. None of these fixed the stumbling/missing issue it has, but like you we get no check engine light. Ours misses under light load as when cruising on the highway at, say, 60-65mph, and at idle, but when we floor it it has all its power & roars off. I'm stumped.

coil pack fixed mine...

After reading dozens of posts blaming coil packs on their stalling/bucking/missing problems, I ordered one this morning & hope to get it before the weekend. Really hoping it works for me too. Thanks!

Changing the coil pack didn't change anything for me. It idles fine, gets normal gas mileage, but it feels like its missing when under light load - like when speeding up on the sidestreets or accelerating on the freeway. It doesn't seem to miss when idling or when floored. Anyone have ideas? Is this a vaccuum leak somewhere? I'd surely appreciate it. By the way - check engine light is NOT on.

Changing the coil pack didn't change anything for me. It idles fine, gets normal gas mileage, but it feels like its missing when under light load - like when speeding up on the sidestreets or accelerating on the freeway. It doesn't seem to miss when idling or when floored. Anyone have ideas? Is this a vaccuum leak somewhere? I'd surely appreciate it. By the way - check engine light is NOT on.

The hesitation problem on my 99 windstar turned out to be a chafed wire in the harness from the PCM to the coil....Each time I replaced the coil, it worked well for a few days or a week or so...Pulled the wiper deck and removed the end of the harness from the PCM...2 of the 4 wires going to the coil, were exposed... attempted to soldier,,,problem appeared to be resolved,, drove it another 2 years…

My 2000 has a horrible miss and maybe the cause of yours. Do you hear a rattling noise on the backside of the engine at idle? a weird thumping sound in the plenum at idle?

Mine turned out to be a broken valve spring on #2 exhaust.

Always had P0302 but then started showing other cylinders missing and well as random misses detected. Once show a lean condition on one bank only, would clear up above 3000rpm, always wanted to die at idle, sometimes had like no power whatsoever (like out of fuel or plugged cats) would always run like crap under 1/2 throttle but full throttle it would try to run much better.

This is a 80k mile windstar by the way .... I did all the changing of stuff you all did and it never got better, I am waiting on new valve springs so can't say if this is entirely the cause. However the way it was you could unseat the valve with your finger tip. My guess at idle compression was blowing into the exhaust which it had a very weird sound out the tailpipe at idle. But once rev'ed up perhaps the lifter tried to pump up and take up the excessive slop in the valve train and thats why it ran better at higher rpm.

with a vacuum gauge connected where the power brake booster line was at idle my gauge would fluctuate very fast between 5" & 10" of vacuum at idle and as it was on the verge of dying vacuum would drop to between 5" and 0" of vacuum and rapidly fluctuate. However it never could exceed 10" of vacuum nor would it ever be steady. I tested the vacuum gauge on my corvette and it read steady at 18" of vacuum and then pulled the valve cover on the back of the windstar and discovered the spring.

http://i186.photobucket.com/albums/x300/jproz1167/windstar/DSCF0181.jpg

http://i186.photobucket.com/albums/x300/jproz1167/windstar/DSCF0185.jpg

I had the same problem with my 2001 Windstar. I changed the coil pack and the problem is gone. The old pack has 6 or more cracks in the plastic housing.

I am having the same problem as some of the above on my 2000 windstar, 3.8 L. It is stuttering/hesitating at light loads but the stutter goes away when you hit the throttle harder. Idles fine. I did just replace the upper & lower intake manifold gaskets because before, it would start up fine on cold engine, but after about 3-4 minutes the rpms would drop, and sometimes even stall off. That is gone now. But the stuttering continues. I since changed the plugs, and the 3 front plug wires. Didnt seem to make a big difference althought the plugs were really corroded, but light in color. So I still have the 3 rear plug wires to change but dont have much faith in that helping.
mark_gober talks about the intake runner control. Mine was disconnected(broken plastic bushings) when I had the intake manifold off. Altough I didnt get the plastic bushings. I just tied some wire around the groove on the arm shaft to hold it in positiion. Maybe there is still too much play for the arms to work properly. I will try to get some of the plastic bushings and see if that helps. :confused::confused::confused: