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Topic Title: 2005 ford freestyle - blowing warm air at low speed
Created On Mon August 02, 2010 9:24 PM
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philso
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Mon August 02, 2010 9:24 PM
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Year: 2005
Make: Ford
Model: Freestyle
Engine Size: 3.0 V6
Refrigerant Type: 134a
Ambient Temp: 100
Pressure Low: 86
Pressure High: 162
Country of Origin: United States

My Freestyle blows warm/cool air at idle works OK at highway speed.

ambient (deg)--Humidity(%)----speed (RPM)-----low press. (psi)---high press. (psi) Dash Vent

100----------------35---------------750 idle--------------86-------------------162-------------------warm

100----------------35----------------1500----------------75--------------------205-------------------warm

100----------------35----------------2000----------------67--------------------255-------------------warm

100----------------35----------------3000----------------53--------------------280-------------------cool

100----------------35--------------750 idle(2)-----------89--------------------180-------------------warm

Idle(2) was taken after the higher speed readings were taken in the afternoon.

I did take a reading earlier in the day at Temp = 84 deg and 65 RH.
The low pressure at 750 RPM was 70 psi with Dash air cool.
The low pressure at 3000 RPM was 40 psi with Dash air cold.
I did not note high press. on the low temp readings.

From reading forums it appears to be the expansion valve or the compressor or both. Also, this scroll compressor has a refrigerant control valve accessible from the back of the compressor that, when replaced has fixed a similar problem for others. Replacing just the valve I think still requires a system evacuation but it is a much cheaper part and compressor removal is not required.

Is there a way to diagnose how many of these parts need to be replaced (1) expansion valve, (2) refrigerant control valve or (3) compressor (contains the control valve). The Refrigerant Control Valve is $30 the compressor is $300+ ?
Or is my problem something else entirely.

Condenser is clean and both electric fans are working.

Edited: Mon August 02, 2010 at 9:42 PM by philso

 
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1stbscout
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Mon August 02, 2010 10:12 PM
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As most of my business revolves around older system before the advent of variable volume compressors I am only guessing here.

Looking at the info It would be my opinion that it is the control valve. The low side is high other than in a small RPM area. The high is low other than in the same area. This would lead me to believe the compressor is not "recovering" the total refrigerant vapor that the expansion valve is allowing into the evap.

Anybody else??

 
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Rick-l
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Tue August 03, 2010 12:22 PM
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i am new at this but trying to understand. Does this car have a thermal expansion valve and what is a control valve?

The plot of High side and low side pressure looks pretty linear vs RPM. How do you tell if the compressor or expansion valve is bad?

 
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HVargas
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Tue August 03, 2010 12:30 PM
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What is your static pressure with the system off and with the 100* ambient temperature.

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When considering your next auto A/C purchase, please consider the site that supports you: ACkits.com
Contact: Arizona Mobile Air

 
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bohica2xo
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Tue August 03, 2010 1:40 PM
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Ok, for starters, I suggest a Mitchell subscription for this vehicle if you plan to work on it yourself.

Mitchell subscription links

That vehicle has a complicated system, and it is packed in tight. To replace the TXV, you start by pulling the strut tower brace... The compressor R&R is about two pages - it starts with putting the car on a lift.

The control system has a bunch of sensors, with pinpoint tests for acceptable sensor ranges. Another 5 pages at least. It is not hard, if you have the step-by-step from Mitchell. If you don't have the FSM tricks in front of you, that vehicle can be frustration on wheels.

Does this vehicle have rear A/C? If so it has two TXV's.

You have a variable scroll. The control valve may be the issue, or it may just be accumulated wear that keeps it from pulling down to where it should.

If the control valve can be replaced without pulling the compressor, that will save a lot of labor. It is a shot in the dark, and might save you some cash. It might also be worthless to change the valve.

A variable compressor system is sensitive to charge level. If you are undercharged, and very close to critical charge the system will behave as yours does now. Without knowing the complete history of a five year old car, my first step would be to suck the charge out of it & weigh it. If it had less than a full charge, I would recharge with a full charge and check the system operation.


I wonder how many of those owners replaced good control valves, and the system worked again with the proper charge level?



Rick:

This vehicle has a TXV (perhaps 2 of them), and a control valve in the compressor. The variable compressors use a control valve that changes compressor capacity based on suction pressure. That low side should be a flat line about 33 psi. A properly working control valve in a properly charged system will have a stable low side pressure, unless overwhelmed by things like a trip to Death Valley...

B.


-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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philso
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Tue August 03, 2010 7:40 PM
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The static press. at 100* amb. is 115 psi. both sides. This is with the engine at ambient also.

With the engine running and AC off the low side will go to 350 psi. after a few minutes. Thats as high as my low side gauge will go. BUT... any measurement over 120 on my low side gauge is guess work. The low side connection is low on the left side, near the firewall in a very warm spot, and difficult to access.

The car is 5 years old, was bought new and the AC is currently as delivered from the factory. No work done prior to now, never had a problem before now. Mileage is 100K.

Thanks for the tip about Mitchell. I have a lift so thats not an issue. I have been rebuilding old cars for about 20 years as a hobby, just never messed with AC before now.

Yes, it has rear AC, do you know if the TXV for the rear is on the firewall with the front TXV? Its not that easy to see with the cross brace in place.

"That low side should be a flat line about 33 psi. " Is the flat line of 33 psi at a 100* ambient?

 
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bohica2xo
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Tue August 03, 2010 9:04 PM
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Well at least you know it is just a normal loss, and it has never had sealer in it.

The rear TXV is in the back at the rear evaporator. You really need mitchell if you have rear A/C too.

I can't find a factory chart on that particular vehicle, but yes in general the control valve & compressor should hold it's own close to 100f or so. Some run out of reserve about 95f. At 1500 engine rpm you should see the control valve maintain steady suction pressure. Reducing or increasing the cabin fan speed should not have an effect on the low side pressure, as long as we are not talking about a car that has been heat soaked to 160f in the sun for 3 hours.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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philso
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I had the refrigerant recovered, there was 18 oz in the system.
Could find no indication of a leak. Tech also took a quick look around and saw no sign of a leak.
I then added another 20 oz to reach 38 oz. as noted on the tag under the hood.

Air at vent is still warm except at elevated RPM (2000-3000)

ambient temp was 98*
relative humidity 36%

RPM-----------low side------------high side

750-------------88-------------------190
1500-----------84-------------------240
2000-----------75-------------------285
3000-----------63-------------------370

Looks like I need some parts?

Edited: Wed August 04, 2010 at 9:11 PM by philso

 
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bohica2xo
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Wed August 04, 2010 10:06 PM
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Well, the 20 ounces went someplace....

Now you need to find out what is going on with that condensor. 370 psi @ 98f ambient says there is a condensing issue. At least you know the compressor is in good shape.

Put the gauges on it, and mist some water on the condensor. Post the pressures. Are the condensor fans working at all?

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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philso
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Thu August 05, 2010 3:20 PM
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ambient temp was 94*
relative humidity 42%

Ran vehicle for about 10 minutes and took the following readings. NO water on condenser.

RPM-----------low side------------high side

750------------81-------------------165
1500-----------71-------------------205
2000-----------66-------------------280
3000-----------55-------------------350

sprayed water over the condenser for about 10 minutes. Pressure slowly dropped from 81 to 72 psi on low side and slowly from 165 to 110 on the high side (@ idle). Sprayed water for another 10 minutes, low side press. stayed at 72, high side press stayed at 110.

Took the following readings.

RPM-----------low side------------high side

750------------72-------------------110
1500-----------65-------------------115
2000-----------60-------------------125
3000-----------49-------------------130


 
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bohica2xo
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With that sort of response, the control valve is stuck at minimum stroke. Even with cold refrigerant the low side did not move much.

The high side is still a problem. With minimum refrigerant flow it should not be 300+ psi. Once you correct the control valve, there will be even more heat in the high side.

What are the cooling fans doing when the high side is 300 psi?

The fans on that vehicle are completely controlled by the PCM. The fans are fed from a 60 amp fuse in the battery junction box. Hot all the time. The PCM controls the fan speed based on A/C pressures, engine temperature, and evaporator temperature.

The fans should be howling if you are running 1500 rpm & 300 psi on a 100 degree day.

Do you happen to have a scan tool? Have you pulled the codes?

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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philso
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The fans have always been running, both of them with a good amount of air flow. I have checked them several times, but not at the higher speeds/ higher pressure. I will do that. The fans could be howling, but then so is the engine.

It will take a couple of days to get the control valve, will post new pressures asap.

I have removed the center plastic cover from in front of the car, what one might laughingly call the grill, for better visibility and accessibility to the condenser. As far as the cleanliness of the condenser, I can see shiny tubes from both sides of the condenser through the cooling fins. Some of the fins at the bottom of the condenser are bent over from bug impacts. This affects the bottom 20% of the fins. This lower 20% may be 25% blocked from bent cooling fins. The upper 80% of the condenser looks straight as new. This would net to a 5% total impact on the condenser fins.

By scan tool, I assume your asking about the codes that are accessible from the connector under the steering wheel. No, I don't have a scan tool but will work on getting the codes.
Will most of the tools sold recover the AC codes if they are present? Or, would I need one with specific capability?

 
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bohica2xo
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This is where you need a reference like Mitchell.

The PCM controls the fan speed by sending a signal to the fan control module. The PCM uses both coolant temperature and refrigerant pressure to make this decision.

The FCM could be failing to run the fans at the requested speed. The refrigerant pressure sensor could be reporting an erroneous system pressure, and the PCM would be acting on bad data. The FCM is a low side control - the fans are connected to the battery, and the FCM switches the ground. A bad or corroded ground could be slowing the fans even when the PCM is requesting full speed. Or the fan motors themselves could just be worn out after 100k miles.

Pulling the codes with a simple code reader is the first step. Retrieve all of the stored codes, and write them down. If you go to a chain parts store, many of them will retrieve the codes. Make sure you get all of the codes, and not the parts guy's idea of what is wrong.

Things like the pressure sensor can be checked in real time with a shop level scan tool. The computer's pressure reading would be compared to the actual gauge reading.

The evaporator does not behave like it is bad internally, and the air side is clean. A few bent fins will not cause those kind of high pressures either.

Once you get a control valve in & working, we can address the high pressures.

I had a quick look at the freestyle forums, and it appears that about half of the poor performers were fixed with a compressor or control valve. The other half are wandering in the dark with vehicles that only cool on the highway, some that actually overheat. There seems to be little understanding about how the A/C pumps heat, and they think the fans are only for the radiator. It looks like Ford incorporated the FCM into the fan shroud, and sells the whole unit - Shroud, fans & FCM as a package.

Like I said before, it is a complicated system. Thank the govt, the EPA & CAFE for that.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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philso
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Wed August 25, 2010 2:09 PM
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Making progress but still not fixed.
The high pressure problem seems to be still with me.
I changed the control valve in the compressor and the system is blowing cool/cold air at all speeds both front and rear systems.

Ambient Temp: 82*
Engine Temp: 185*
Static press: 92 psi - both high and low- taken prior to starting vehicle, engine cold.

RPM Low High
700 50 250
1500 42 310
2000 38 350
3000 32 pressure climbs steadily to about 420 psi, and system shuts down.

AC pressure relief valve "close pressure" is spec'ed at 450 psi.


with water running over the condenser...
RPM Low High
700 51 175
1500 42 200
2000 35 225
3000 32 280

There are no DTCs posted or pending.
I do not detect a change in fan speed at any RPM/Pressure.

With the AC off the fan cycles ON at an engine temp of about 210*F and cycles OFF at about 200* F.
The thermostat (by spec) begins opening at 183* F, and is fully open at 203* F.

With the AC on the fan runs continuously.

 
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bohica2xo
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Well, either high side pressure transducer is not reporting an accurate pressure to the PCM, or the fan control is bad.

The fans should have noticeable changes in speed over that pressure range.

There is a test range for the sensor in the service manual, or you can just replace it. The fan control is only sold with two new fans as an assembly. A bit harder to test without some dealer level equipment too.

Definitely a condensor airflow problem.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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1stbscout
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Did you get this system working any better?
The info you have now leads me to believe you have one of two or three problems, possibly all. The high side pressures at 82 ambient are higher than I would have expected. With water over the condenser (guessing your water to be at about 68*) the high side should be considerably lower than the numbers you have posted.

1. The condenser is partially plugged. Even with water over the surface the high side pressures are a bit higher than what I would have expected. What are the inlet and outlet temps?
2. The compressor is "bad". The high side pressures could be caused by a compressor with an internal "leak". This would cause it to "recompress" the vapor which in turn will drive the high side temps and pressures up.
3. System is charged slightly wrong. The little I know about the variable systems has been gleaned from this site and studying the theory of operation on them the past couple of weeks. So if I am understanding properly the charge level is quite critical on these newer system in order for the control valve to operate properly.

Mind you I am not discounting the possibility that the fans are not keeping up with the demand. Just saying with water flowing over the condenser the fans are not nearly as important. The water will do the cooling even if the fans are off. I would think you need to find the problem with the high side pressures/temps before you continue. As this can be caused by a number of things I am not sure where I would advise you start first. Personally I would not spend any more money until you have a good idea where the problem is.

 
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1stbscout
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one other thought just occurred to me. It is possible that your TXV's are helping the problem as well. What temp is the high side line entering the TXV? Temp of the line entering the evap? Temp of the outlet of the evap?
Although the system pressures are what we use to do a "quick check" it is the pressures and temps that really tell you what is happening and help the troubleshooting process.

There are several understandings that are needed for this. The first and most important is how the refrigerant does it's work. How much (for simplicity) heat it can store at the various temps and pressures.

With a TXV the amount od subcooling is usually more important than the superheat BUT they should run hand in hand.
Simply put subcooling is the difference in the temp shown on your high side gauge and the actual temp of the high side liquid line.
Superheat is the difference between the temp on your low side gauge and the actual temp of the outlet of the evap.

Most systems (very general statement here as the designers may have had other ideas ) are designed to have between 5 to 15* of subcooling and right at 10* of superheat.
The TXV is designed to maintain these numbers by choosing an orifice size and a spring size to maintain proper "flooding" of the evap with liquid refrigerant. under a full load the TXV should be wide open. The bulb is intended to reduce the amount of refrigerant if the load on the system drops in order to keep liquid refrigerant from making it back to the compressor.

With the info you have provided for example at idle with water flowing over the condenser (Assuming 68* water) you would have ~ 47* of subcooling and the core temp should be very close to 56 degrees. Assuming a properly operating system with 10* of superheat the outlet of the evap should be at ~ 66*

As you can see the subcooling number is way high. This can be caused by several things the biggest of them listed in my other post.
If your evap outlet is different than the above number by more than 5* there is a different diagnosis as well.
This is why the temps and not just pressures are needed to properly determine what is wrong with the system AND, although some may disagree, the proper charge level for YOUR system.

 
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bohica2xo
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Philso:

The first line of your first post "My Freestyle blows warm/cool air at idle works OK at highway speed." - is a classic description of a condensor airflow problem.

In addition to that issue, you also had a failed control valve, and were 20 ounces low on refrigerant. As I predicted, once you solved the valve problem & charged fully - your high side pressures got ugly.

There is nothing wrong with your compressor - it manages to push 400+ psi. The performance is typical of a scroll with a few miles on it, performance is directly related to compressor speed. If you were to set the cabin fans to the lowest speed, you would see the control valve pick things up at a lower rpm.

After looking at the diagnostic chart again, I will say that the pressure transducer is probably OK, based on the compressor shutdown @ 400 psi.

Sure, the condensor could have some blockage - but from what? The compressor is original, and scroll compressors that shed enough material to block condensors usually do so on the last 10 revolutions they ever make.

If you have long enough gauge lines, duct tape the gauges to the windshield & go for a drive. If the 60 mph air blast is enough to keep the pressure down to reasonable levels, it can only be the fans.

That vehicle has a lot of glass, and two evaporators. It never had really low condensor pressures, but it should have enough fan to keep it from dropping the compressor on a 115f day.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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1stbscout
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Mon August 30, 2010 1:20 AM
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bohica

Without trying to be antagonistic, I believe you are on the right track but have missed some very important information that was given.

Quote

sprayed water over the condenser for about 10 minutes. Pressure slowly dropped from 81 to 72 psi on low side and slowly from 165 to 110 on the high side (@ idle). Sprayed water for another 10 minutes, low side press. stayed at 72, high side press stayed at 110.


The key in my mind is the speed with which the pressures dropped. It would not be uncommon, depending on the evap load, for the low side to take a few minutes to drop. But the high side should drop almost immediately at least within seconds of the water being run over the core. The time delay indicates to me the condenser is not working at max efficiency. With the water flowing over the core the fans could be disconnected and the pressures and temps should not rise nearly at all.

Anyhow... as philso has not posted lately I have to assume this thread is finished.
 
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philso
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I invested in some additional software for my scan tool and now know the AC pressure transducer is working fine.
The OBD monitored pressure runs consistently about 20 PSI higher than the gauge pressure. The sensor is located at the compressor, the gauge port is a couple of tubing feet away.
I agree that with the system shutting down due to high pressure it was a strong indicator, but I was not ready to accept a single data point as confirmation. With the new software I am able to monitor the Ford enhanced PIDs, one of which is the AC Pressure sensor.

I also now know the Engine Temp. (which we already knew) sensor is working well and the Evaporator Temp. Sensor is working well.
These are the inputs to the PCM that drive the fan duty cycle from the PCM to the FCM.

I also measured the volts to the fan at the fan connector between the FCM and the fan itself, this with a meter. While at idle with the AC on this typically runs 8 to 9 volts, it does ramp up to Vbat when the RPM and the AC Pressure increases. With the AC off the fans only run briefly at 8 to 9 volts to drop the coolant temp. below 200*

I did mislead when I said previously the fans do not change speed, I looked more closely after measuring the voltage and they do change speed but in my judgement the speed change is very small. I don't have a strobe so am relying on airflow change that I can hear and feel.

With regard to the fans I am monitoring...
FANDC_____Variable Speed Fan Duty Cycle..........%_________7.5 to 86% (full range)
FANVAR ___Variable Speed Fan Level...................%_________0 to 100% (full range)
FANVARF___Variable Speed Fan Output Fault....YES/NO______This always shows "No Fault"
FANSSM____Fan Speed Sensor Monitor............LOW/HIGH____This always shows "LOW"

Mitchell does not give much information on these PIDs but I think the FANDC is the output from the PCM going to the FCM.
I am not sure what FANVAR is measuring but it tracks FANDC fairly well but consistently shows a lower % reading up to about 65%, they track together from 65 to 75%, then FANDC tops out at 86% and FANVAR continues rapidly to 100% before topping out.

Driveway measurements....
PID______________750______1450________2000________3000
FANDC_%__________64_______82__________83__________86
FANVAR_%_________67_______100_________100_________100
AC Press(OBD)_psi__286_______335_________352_________436 (compressor shut down)

The low side tracked to the values given previously (gauge readings).
_psi_____________52________44__________36__________32

Driving Measurement.........
I monitored the AC Press with the OBD meter.
Driving for a couple of miles stretch on the highway at 60 to 63 MPH
RPM varied a little but typically was at 2000. This vehicle has a CVT and RPM is not always under direct driver control.
AC Press was 230 psi.
FANDC was 7.5%
FANVAR was 0% Net. there was no fan running at this speed.
The evaporator air temp. was 43*F to 45*F.
I did not monitor low side press.

As I slowed down the fans ramped up.

I am monitoring the available AC fault PIDs. All show NO FAULT. There are no fault codes Stored, Permanent or Pending.

It appears more air over the condenser would definitely fix the high side pressure problem. As you have said for a while, this is likely the problem. I think the next step is to replace the fans. Not a cheap undertaking in this vehicle. I wish I understood a little better exactly what the PIDs were measuring. But I seriously don't want to have to replace the PCM. Even with the pictures in Mitchell, I have not been able to find the PCM.

 
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fasto
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Mon August 30, 2010 10:36 PM
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Philso, very interesting. Although I drive a VW I had many of the same challenges that you're having. Stopped or moving slowly the AC would cycle on the high pressure trip. Driving it was always OK.
Regarding the fans:
1) Are there any idler fan blade sets? On some cars a second fan propeller is belted to the main fan propeller. This belt can go missing, and you have the driven fan running but pulling air from in the engine bay (through the stopped idler fan) not through the heat exchangers. My car is made like this, and that blasted little belt fails about once a year.
2) Are the fan blades in good shape, or are they broken or worn?
3) How's the condition of the baffles and shrouds under the car? I found a missing shroud (well, I found that it was missing...) on my car. This missing shroud allowed the fans, while running like crazy and moving a ton of air, to simply recirculate the air in a small loop under the bumper. The fan would pull hot air from inside the engine bay under the bumper and around through the grille. When I put my hand under the bumper this moving air was at least 150degrees, but blowing like crazy just circulating through the radiator & condenser. When driving this would not happen.
If you have access to "smoke candles" like used in buildings to troubleshoot airflow you might check to see where the intake air is coming from, and where the exhaust air is going to. You can get these smoke candles at a shop that sells to the contractor heating & cooling trades or at McMaster-Carr. I don't think you'll find them at Home Depot. It should be a little quicker and cheaper than replacing the fan set, I'd think. You could also stick a thermocouple in the air stream right at the front of the condenser - don't use an infrared thermometer, you want to measure air temperature, and don't touch the condenser. Do this at many locations in front of the condenser, especially down the bottom corners. The temperature should be only a little more than ambient temperature. If it's way high look for missing baffles and such under the car, the dealer service techs like to throw them out instead of reinstalling them (takes too long, you know).
Oh, the PCM is probably inside one of the front fenders. You probably have to take the fender off to get at it.

 
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bohica2xo
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Tue August 31, 2010 12:15 AM
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Philso:

Excellent work. All that OBD stuff does come in handy sometimes.

It looks like everything is working well enough at highway speeds. Fasto has a valid point, if you are missing an air dam it could be recirculating a bit with zero vehicle speed.

The only thing that jumps out at me is the "FANSSM" always showing "Low". The fan controller & PCM seem to be doing their jobs, but the fan speed feedback is not seeing a large enough speed increase to show a change. The fan motors themselves could be tired, worn brushes / bearings etc.

Unfortunately the factory does not provide an RPM range to check fans against. If you happen to have a photocell tach (or can borrow one, most R/C flyers own one) you can check the blade count at FANVAR 100% before you replace the fans. It would be interesting to see how much difference there is. I have seen this happen with SAAB cars, the fan motor gets tired and when it drops 15% overheating begins. Not much reserve.

100k / 5 years can be a lot of time on a fan if you spend much time in traffic. The Freestyle is not very common here in Las Vegas, so I can't say for sure what the fan life is typically. Saturn fans seem to go at 110k to 130k around here - about the time the A/T fails, a chicken / egg deal for sure.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

 
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Rick-l
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Posts: 32
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Tue August 31, 2010 12:13 PM
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Holy crap this is fascinating.
There is some service magazine that has an article like this every month, you could submit it.

 
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philso
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Tue August 31, 2010 1:46 PM
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B,
Thanks for all of your help on this.
Will let you know how things work out with the fans.
I do like playing with the OBD scanner, but then any opportunity to invest in a useful tool is always welcome.

I found an on-line source that has a good price for the fan assembly. $145 instead of the Ford $430. I think that is enough difference to justify using the aftermarket part. It will take a week or so to get the fans. Plus other life events keep getting in the way. This is my daughters car and I loaned her my extra vehicles to use while I am working on hers so getting it running by tomorrow has not been a factor in this repair.

I agree with your comments on FANSSM, I just wish I knew what it was monitoring for sure.
Per Mitchell, the Ford docs have several holes with regard to the AC info. for this vehicle. Like no Suction/Discharge pressure curve. And missing info on several of the AC PIDs.

Referring to earlier comments....
I am confident the refrigerant is full. The system has been evacuated and filled twice. The first time we found the low charge. The second time (after the charge had been topped up) to replace the control valve. The second time it was evacuated, the charge was exactly where it was suppose to be at 38 oz. (per the tag under the hood). I saw the setting on the machine when it was recharged the second time (2 lbs 6 oz plus 2 oz for hose loss, as per the equipment spec.).


Fasto,
Thanks for your comments. I have checked the various air deflectors and foam seals around the condenser/radiator and compared what I have to the Ford pics, but will do so again to confirm. The fans while expensive on this vehicle are easy to remove. I have removed and inspected and see no obvious problem. I have the Ford pictures (through Mitchell online) of where the PCM is but I still can't see/find it. I know there are three connectors for the 150 pin PCM. Probably does not matter at this point as I don't plan to do anything with it anyway.

 
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fasto
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Tue August 31, 2010 5:01 PM
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philso, the missing shroud on my car was only about 2-3 inches wide and 30-ish insches long. It seals the back/bottom of the bumper to the radiator core support and forces the airflow through the front grille instead of from under the car. It was not obvious that it was missing.
From my research the PCM on the freestyle is in the "cowl" area, where the windshield wiper linkages are, sort-of on the passenger side, underneath a plastic grill of some sort.

 
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