Automotive Air Conditioning Information Forum (Archives)

salth2oj on Sun July 17, 2011 2:38 PM

Year: 2004
Make: Ford
Model: Freestar
Engine Size: 3.9l
Refrigerant Type: 134a
Ambient Temp: 92
Pressure Low: 50
Pressure High: 200
Country of Origin: United States

Hello All,
I’m looking for a little assistance or direction on my A/C problem.
I have a 2004 Ford Freestar and since the day I picked it up from the dealer I had prefect ice cold air conditioning. In the 7 years that I had the van, not one thing was done to this system.
Last week I noticed that the air was not as cold as it once was and now has gotten to the point to where it just blows cool. I also noticed that when the compressor is on, I hear a “knocking” noise coming from it.
I just pulled out my gauges and I’m finding that the low side is at 50 psi (very high?) with the engine at 2k RPM. The high side is at 200psi. The outside temperature is about 92 when these reading were taken.

Any ideas what might be going on?

Jim

tony1963 on Sun July 17, 2011 4:54 PM

Yes. Over the years, you have lost some refrigerant and oil due to normal leaking. Instead of servicing the system, you kept running it and low lubrication has led to compressor wear, and noise.

I wouldn't boast too much about going 7 years without trouble since it also says that you haven't done maintenance on the system, either.

Every two years, it is a good idea to change the drier and add a small quantity of oil to compensate for what will leak out.

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Grove Automotive Group, Inc.

An Alabama Corporation

salth2oj on Sun July 17, 2011 9:06 PM

I wanted to give as much history (good and bad) as i could, not boasting.
I'm just trying to understand my next move on getting this system back working as it once did.

Any ideas?

Jim

Quote
Originally posted by: tony1963
Yes. Over the years, you have lost some refrigerant and oil due to normal leaking. Instead of servicing the system, you kept running it and low lubrication has led to compressor wear, and noise.



I wouldn't boast too much about going 7 years without trouble since it also says that you haven't done maintenance on the system, either.



Every two years, it is a good idea to change the drier and add a small quantity of oil to compensate for what will leak out.

bromodragonfly on Mon July 18, 2011 12:52 AM

I would verify that the knocking is coming from the compressor internals, and not caused by the pulley or belt in some way.

If it is, at the very least, you'll be looking at a new compressor w/ new oil, new drier, and fresh refrigerant charge. If you have an orifice tube, it should be replaced. If TXV, it should be either replaced or inspected for any debris that could plug the orifice.

The compressor hasn't failed yet. So it all depends on how often you've been running it with the knocking sound, and how much money and time you want to spend. Hopefully the compressor hasn't worn out too badly, and debris and junk in rest of the system is minimal.


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There is no knowledge that is not power

salth2oj on Wed July 20, 2011 7:17 AM

I'm slowly obtaining the parts needed for this repair.
I have a new compressor, oil and a orifice on hand. Four cans of R-134a from Walmart. A new dryer is on its way. With any luck, I will get a chance to install them over the weekend.
Wish me luck.