Ford five hundred a/c problems

Blend air door is electric in this car.

Well, there goes that theory.

mcparadise thanks for your response, I failed to mention that it seems the air temp on the right side of the car feels slightly warmer than the left side vents when this happens. The expansion valve was replaced, and I will state what was typed on my invoice, “performed a/c perfomance test, ambiant temp @80 degrees. Duct temp @70degrees. Hooked up gauges and found low side pressure was 60psi and high side pressure at 120psi. Expansion valve stuck open. Need to replace expansion valve, evacuate and recharge system.” This was done, unfortunately we had a cold front come through as this was being performed and the outside ambiant temp dropped into the upper 40’s and the tech was unable to check if this worked. Yesterday it was back into the mid-80’s and could tell that it didnt. I am dropping the car back off tonight to have it looked at tommorow, tommorow in D/FW it is supposed to be 65 degrees so we will see.

Bad compressor?

I have been researching and I guess Fords are known for blend door failures, even the electronic ones. Two questions, Does anyone know were the blend door is located on my vehicle? It seems that most accessories (blower motor and various swithes) are faily easy to reach behind glove compartment and in passenger compartment? Would the compressor be bad if it works at anything above idle?

Can you always get hot air out when you set the control to hot? Does it then always return to cooler air when you set it to cold? If so, it is probably not the blend air door. If you have auto climate control, then there is a diagnostic test that you can run from the control head to verify the blend air door operation.
My theory is that the compressor is not pumping enough, and that is why the mechanic was fooled into replacing the expansion valve. The faster the engine speed, the more the compressor will pump. Another thing to check is the engine cooling fan. It should be at full speed at idle with the AC on.

How are the pressures looking now?

Yes, I can always get hot air when I set it to hot and it does always get cooler when I go colder. I do have auto climate control, is the diagnostic test something I can do myself or just the dealer? I dont know what my pressures are at this time, (no gauges). I did find a TSB for 2005-2006 five hundreds #19107, mine is an 2007, for noise in the passenger compartment-air inlet door inoperative (recirculation). Could this possibly explain my problem? Are TSB’s handled at Ford’s expense? or are they just guidelines for the tech to work on. If I would still have to pay, I would try to put it on myself. I called the dealership and the door actuator is only $33.00, I would try to put it on myself if I knew were it is, anyone know?

TSB’s are guidance, you need a pressure check. With both high side high and low side high this can indicate a “flooded” evaporator which can indicate a defective expansion valve. I can’t fault them for replacing the expansion valve. We need to see pressures now.

It is back in the shop that replaced the expansion valve. The ambiant temp in D/FW today is only going to be around 70 degrees, so this might hurt them in diagnosing the problem. I will keep you posted.

Before making much of a guess at this I would need to know what the high and low side pressures are; preferably at elevated RPMs. (1500-2000)

I’m a bit surprised that Ford used an expansion valve on this car. Thought that Ford pretty much went the orifice tube route on everything starting over 20 years ago. ???

My Lincoln LS’s use expansion valves. I can find other recent Ford examples too.

Back from the shop, after a day and a half unable to diagnose the problem. Outside ambiant tempatures in the mid 60’s by afternoon is not hot enough to cause a big need for a/c. Will take it back in about a week when temp’s are to be warmer.

I have this same problem on a 2005 Five Hundred, I was assuming it was just low on Freon and was ready to recharge it today but the fill valve is almost impossible to get to…I came online trying to get ideas on how to do this when I stumbled across this post…now I am concerned that it may not be low and I have a bad compressor. I am in Florida and need A/C, it cools fine while driving but at idle it immediately gets warm.

willettj,

I still have not had mine fixed, I live in the D/FW area and it has not been consistently in the 80’s yet to have them diagnose it. Unfortunately here it will go from mild to 90’s in a couple of days. I originally took mine to a independent a/c repair that has been around since the 1960’s with the same owner. He hooked gauges up and spent about 10 minutes with my car and diagnosed it with a bad compressor, 2 days, $1000.00 dollars and lots of work on his part. He didnt seem too excited to tear into my car and I wasnt too excited to spend $1000.00 without a second opinion. That is when I took it to the place above that diagnosed a bad expansion valve, and $286.00 dollars so I was happy to pay this. This did not fix the problem. I am back at square one, waiting on the temp’s to get warm. In my post above I found TSB #19107, have you had the dealer look at this as a potential cause to your problem? It covers your year model. Have you done lots of idling in your car since you have had it? I have, I am in sales and when I am on the phone and writing I always pull over (lots of times with temps in the upper 90’s to 100). Someone told me that idling for extended periods of time is suicide for an a/c compressor. Have you had yours in the shop at all? What did they say?

Now you have crossed the line, the ambient temp does not have to be in, what are you saying mid-80"s for diag. Never heard the “extended idle” warning. I do know that life is tough for a AC compressor.

oldschool, I get what your saying about the temps. Only thing I can say is that when I have taken it in once for the expansion valve diagnosis it was 80 at diagnosis and in the mid 40’s when I picked it up, unable to tell if that worked until it warmed up. Dropped it back off at the shop for second time and it was 82 at drop off, cold front came through that night and it did not get out of the 50’s as the high and upper 30’s for lows for 3 days. I was told that since the electronic temp control only goes down to 60, that the computer was not calling for a demand for a/c since the temp in the car was already colder than 60, therefor the mechanic or myself could not tell whether the a/c was warming up or not since it was cold outside. Whether this is correct or not, I dont know. I am going on what the tech said, but I dont need my a/c when I have the heat on.

No idea what’s going on here since info about pressures, etc is not known but inspecting the A/C for proper operation should not require a hot day to do it.
Even on a cool day, if the pressures are correct the evaporator outlet tube should be very cold and sweating.

Idling on a hot day is not suicide for an air compressor. Matter of fact, the compressor will work a bit easier at idle than at elevated RPMs. When the RPMs go up the high side pressure also goes up a bit. This means the compressor is working harder at speed.

If you can determine what those high/low side pressures are both at idle and at elevated RPMs and post them, this may help in at least formulating a wild guess.

65 is the low setting on the climate control. 60 is an override setting that puts the climate control into manual max cooling mode. When set to 60 it ignores the interior/exterior temperatures. You need to find better mechanics.

Back at the shop, unfortunately I have $300.00 invested in this problem and still not fixed. Mechanic says that he thinks it is the “thermo-transducer” sending a false reading to the computer, thus cutting off the compressor.(his friend at the dealership said he has seen (3) five hundreds with this problem) I was told that the part is under $50.00 and he will put it on at no charge since the expansion valve fix was not the problem. Any ideas on this? willetj have you gotten yours fixed? what was the problem?