Hi all,

Well everyone here has been a help with my coolant flush issue and I'm set to go on it this weekend. I'm trying to get the van in shape before the first snow flies. I've only had it a few months some I'm trying to get familiar with it.

One of the things that has been bugging me is a low speed steering puff. When doing slow speed maneuvers in the driveway (forward or backward) and I turn the steering wheel there is a puff sound. It is somewhat odd. When I start the vehicle for the first time I can hear coming from the drivers fender area a sound similar to a vacuum. After a short time of idling it lessens and stops. I just assumed it was a reservoir of some type. However, when I turn the steering wheel at low speed the puff sound if very similar to that I just described but brief, like someone saying the 'P' sound.

Now, I asked my dad (former mechanic) and even though his hearing isn't as good as it was he figured it was a valve of some type in the steering box. I forget exactly how he described it but that is the gist of it. Now that made me think, is the thing sticking? Maybe it binds, breaks free and causes the puff.

Without trying to complicate the situation, when it makes the puff sound that causes a load on the engine, the idle increases and the car lunges forward. I thought the IAC may have been a problem but I cleaned it out without any change. The idle does quickly return though. There is also a vacuum bleeding sound from the passengers side when the idle returns which sounds like it may be the vacuum pressure regulator but I am just guessing. I have no scan tool yet.

The people who had the car before me had a PS hose replaced (complaint: hard steering) which makes me think that maybe they drove it without fluid for a bit after that hose went. Or, possibly, is the box really gummed up and the thing sticking? Should I flush it using the Ford procedure?

Any ideas on this odd problem would be appreciated....

Hi all,

Well everyone here has been a help with my coolant flush issue and I'm set to go on it this weekend. I'm trying to get the van in shape before the first snow flies. I've only had it a few months some I'm trying to get familiar with it.

One of the things that has been bugging me is a low speed steering puff. When doing slow speed maneuvers in the driveway (forward or backward) and I turn the steering wheel there is a puff sound. It is somewhat odd. When I start the vehicle for the first time I can hear coming from the drivers fender area a sound similar to a vacuum. After a short time of idling it lessens and stops. I just assumed it was a reservoir of some type. However, when I turn the steering wheel at low speed the puff sound if very similar to that I just described but brief, like someone saying the 'P' sound.

Now, I asked my dad (former mechanic) and even though his hearing isn't as good as it was he figured it was a valve of some type in the steering box. I forget exactly how he described it but that is the gist of it. Now that made me think, is the thing sticking? Maybe it binds, breaks free and causes the puff.

Without trying to complicate the situation, when it makes the puff sound that causes a load on the engine, the idle increases and the car lunges forward. I thought the IAC may have been a problem but I cleaned it out without any change. The idle does quickly return though. There is also a vacuum bleeding sound from the passengers side when the idle returns which sounds like it may be the vacuum pressure regulator but I am just guessing. I have no scan tool yet.

The people who had the car before me had a PS hose replaced (complaint: hard steering) which makes me think that maybe they drove it without fluid for a bit after that hose went. Or, possibly, is the box really gummed up and the thing sticking? Should I flush it using the Ford procedure?

Any ideas on this odd problem would be appreciated....

Hello chasealley: Is it possible the power steering box is over filled and needs to be bleed. If so take the dip stick of and move the sterring wheel left and right a by a turn or two then check fluid level, do not over fill

Thanks for the reply. I should have mentioned in the last post that I followed Ford's procedure to bleed air from the pump already -- thinking that whoever replaced the hose didn't do that. Turns out it was done at Ford. Bleeding the pump did alleviate some of the pump noise and sounded generally smoother but the puff is still there.

Thanks for the reply. I should have mentioned in the last post that I followed Ford's procedure to bleed air from the pump already -- thinking that whoever replaced the hose didn't do that. Turns out it was done at Ford. Bleeding the pump did alleviate some of the pump noise and sounded generally smoother but the puff is still there.
Is thier some sort of adjustment screw behind the power steering pump, and check for some type of electrical switch attached to the pump or hose connection. Also check if there are leaks under the car near the power steering system. If there is put a piece of newspaper under the car to help you identify the stain for diagnosis.

Mine does the same puff noise when turning the steering and also when I start the vehicle for the first time, I can hear the loud vacuum sound coming from the drivers fender area. And same as yours after a short time of idling it lessens and stops.
All except for the puff sound causing a load on the engine, then making the car surge forward... I don't get that.
Have you figured out yours already, if you do pass it along?

Mine does the same puff noise when turning the steering and also when I start the vehicle for the first time, I can hear the loud vacuum sound coming from the drivers fender area. And same as yours after a short time of idling it lessens and stops.
All except for the puff sound causing a load on the engine, then making the car surge forward... I don't get that.
Have you figured out yours already, if you do pass it along?

Hi Ed,

Thanks for the post. I haven't got mine figured out but it is up there on my list of things to do. I do have a stethoscope to help me pinpoint the sounds, I just need an assistant to turn the wheel while I crawl around. There are a lot of things happening in there that I can't seem to differentiate. Well, I thought that before, but I'm beginning to think they may be related. I've got the steering puff noise, the vacuum noise on start, the load on the engine causing an idle fluctuation and upon settling another vacuum sound possibly from the vacuum regulators.

So far I suspect this all to be related. I'm working on getting the AutoEnginuity scan tool to see what the system is doing. I'm also hoping to get that assistant so I can pinpoint those noises to a specific part very soon. I'll keep you posted.

Hi All
My wife's van a 2001 Windstar has the same puff sound when turning the
steering wheel. All fuild levels seem full. Have you been able to discover the
problem. Thanks

Well, I didn't get it figured out yet but I did make some progress.

Today I went out with an assisstant and a stethoscope. It seemed that I was able to hear that puffing sound in a couple locations. The first was around the upper intake manifold near the throttle body. I'm not sure why.

The second place I heard the noise (and my assistant) was in the drivers fender. I stuck the steth along side the air inlet and sure enough it was in the fender. After peeking inside the fender it appeared the only component in there was the air inlet tube that goes to the throttle body!

This had me a bit interested so I removed the MAP sensor body from the air filter housing and sure enough, my assistant turned the wheel and the sound got stronger. Strong enough to suck my hand in!!

So it appears that the 'puff' sound we are hearing is nothing more than rushing air. The noise is amplified because it is occurring in a closed space near to the driver. There is very little insulation between that inner fender and the door, and in my case it is falling down making the noise a bit louder. The fact that the idle changes and returns quickly says the IAC is not sticking.

However, this still leaves us with the question "why the heck does it puff in air when the steering wheel is turned?"

I have a couple theories that need further exploration but here they are. The first is that the steering pump may be going bad or that a hydraulic component along the way is sticky or failing. This causes such a high demand on the engine that it compensates by rushing in that air (and gas) to keep the engine from stalling. If the IAC is working right it should happen so fast that you shouldn't notice it - and the idle should stay pretty much the same. Now, if there are other items that also add load to the engine at the same time then this will be further increase. I have a failing alternator bearing and idler arm pulley bearing as well.

The second theory is that there is still air in the power steering fluid. I did the Ford Factory bleed procedure but my vac pump was old and didn't seem to hold vac. I should maybe buy a new one and try again.

This is from a Ford TSB about power steering noises:

NOTE ONE WAY TO CHECK FOR AIR IN THE SYSTEM AFTER EVACUATION PROCESS IS TO MARK THE FLUID LEVEL ON THE POWER STEERING RESERVOIR PRIOR TO STARTING THE ENGINE. IF THE FLUID LEVEL DROPS WHEN THE ENGINE IS STARTED, THERE IS STILL AIR IN THE SYSTEM.

I'll have to try this and see.

I still need to get my hands on a scan tool and see what else is going on in the system. Developing....

It could be a pressure sensor problem. It's supposed to raise the idle while turning at slow speed or at a stop to keep from killing the engine.

It could be a pressure sensor problem. It's supposed to raise the idle while turning at slow speed or at a stop to keep from killing the engine.

Thanks for that. I wasn't aware of the pressure sensor. I did see a component attached to the PS hose that is probably what you are referring to. I'm wondering if a bubble of air around there is possible? Also, I'm wondering if anyone who has performed the "sludge removal" purge and refill (according to Ford's manual) has bothered to take out the sensor/switch and if so, was it gummed up, or is it even cleanable?

As for what it is sending to the PCM, I'll check that out when I get a scan tool :) Soon I hope...

the noise is considered normal - I have had many customers complain about it but due to the cheap plastic intake any air changes are very obvious to the ears - the p/s pressure sensor changes the idle speed and iac strategy - sometimes cleaning the throttle body and iac ports will help with the noise but is unnessessary.

Yep, the suction noise from the driver's side fender is very noticable on the 1999+ windstars due to the position of the inlet to the air cleaner. It's VERY loud on a cold startup with the drivers door open.

Joel

Thanks rivguy and Joel,

When I peeked into the fender I could see just a piece of jagged plastic on the end of the air cleaner sticking straight into the fender. I have a good book here called 'Master handbook of acoustics' which discusses fine tuning noise in chambers (like a muffler). Basically, the Ford method sucks!

I had a Saturn a while back and from the air cleaner (big box with a reserve in the bottom) was a line the went out the front of the car. Much quieter. Ford could have put an edtension on that tube and aimed it toward the headlight or around in front of the rad.

Now, I cleaned my IAC a while back and it was free from gum. I didn't do the throttle body because I didn't know what to use, if it was teflon coated, or whatever. basically, didn't want to screw it up. What is good to use on these to clean them and not remove the protective coating? I did that once to a relatively clean TB and it carbon'ed up real quick after that.

Also, What could be causing the lurching? When the steering wheel is turned so far the pressure becomes great enough, the pressure switch kicks in and the idle pushes to around 1000 rpm briefly (hear that puff) then back down, usually dropping a bit too much, then back to normal idle. This is troubling when doing slow speed manuevers such as parking because that PS switch raising the idle causes the vehicle to jump.

Any idea where to look first?

I have noticed unusual sounds from our '00 Windstar when moving very slowly (like reversing in/out of the driveway). I feel a bit of a lurch while making a sharp turn at these low speeds also... I'm praying it's just tire resistance on the pavement.

Please, God, just let me get my transmission issues fixed and the heater blend door situation resolved before throwing me another Windstar curveball!
Amen.

I have noticed unusual sounds from our '00 Windstar when moving very slowly (like reversing in/out of the driveway). I feel a bit of a lurch while making a sharp turn at these low speeds also... I'm praying it's just tire resistance on the pavement.

Please, God, just let me get my transmission issues fixed and the heater blend door situation resolved before throwing me another Windstar curveball!
Amen.

Ya, there's always something causing problems with cars.

As for the lurching. If you want to see if it isn't tire resistance, just watch the RPM on the dash. Mine jumps to about 1000 when lurching. Back down after the steering pressure breaks.