Service time for 2005 QP!

ChrisNico

Member
Messages
171
Hi there guys & girls,

It's that time again, and looking through the service schedule, I've only just noticed that for Air Conditioning it states "Replace coolant and filter every 2 years". Is this really necessary?

Additionally, does steering fluid 'age' or does it deteriorate with use? I have done very few miles since it was last replaced.

Thanks in advance for any advice,

~Chris
 

conaero

Forum Owner
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34,594
I believe you may be quoting the engine coolant, that’s a two year item. AC regas is done as a 4 year major service item.
 

ChrisNico

Member
Messages
171
I believe you may be quoting the engine coolant, that’s a two year item. AC regas is done as a 4 year major service item.
Hi Matt. According to my service book, it’s every 2 years. Maybe they lengthened it on later cars. Still, I’ve had the car for exactly 4 years and have never serviced the A/C so I guess I should do it, right?

Cheers,

~C
 

conaero

Forum Owner
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Well you could employ the ‘it ain’t broke, don’t fix it’ rule here but I would say 4 years is a realistic expectation.
 

Zep

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9,110
@Zep to the freon coloured courtesy phone, please. @Zep
:)

C

Haha.

Refrigerant doesn’t get old (Christ knows it lasts well enough in the atmosphere) so as Matt says, if it ain’t broke don’t fix it.

You are more likely to introduce contamination by doing the change than leaving well alone. But if you have a leak, fix it, moisture will get in and that’s where the trouble starts.
 

ChrisNico

Member
Messages
171
Haha.

Refrigerant doesn’t get old (Christ knows it lasts well enough in the atmosphere) so as Matt says, if it ain’t broke don’t fix it.

You are more likely to introduce contamination by doing the change than leaving well alone. But if you have a leak, fix it, moisture will get in and that’s where the trouble starts.
Thanks for that! Strange that it’s part of the service schedule

Looks like I’m leaving it alone then. Cheers!
 

philw696

Member
Messages
25,123
As an A/C certified technician there is no harm in giving the system a service.
The gas that comes out gets recycled in a automatic modern machine.
It will be low guaranteed so you know you will have the correct amount back in.
I bet your car still has the original receiver drier which is the filter.
My recommendation would be change that and it will be good for another 16 years.
 

Zep

Moderator
Messages
9,110
As an A/C certified technician there is no harm in giving the system a service.
The gas that comes out gets recycled in a automatic modern machine.
It will be low guaranteed so you know you will have the correct amount back in.
I bet your car still has the original receiver drier which is the filter.
My recommendation would be change that and it will be good for another 16 years.

I hear you Phil, but the need to change the refrigerant is a marketing ploy for a few reasons. R-134a is a hydroflourocarbon with an atmospheric lifetime of 14 years. That means, when released into the air it takes 14 years to breakdown in the atmosphere subject to UV light and other atmospheric processes. In a hermetically sealed system such as a car its life, providing the seals stay in good condition, it is pretty much indefinite. I could show you 15 year old fixed A/C plant with the original refrigerant that is working as well as the day it was installed. Every time you access a service port on any refrigeration system, there is a risk of introducing contamination, a small amount of air, a little bit of crud in the port itself and the real enemy, moisture. Then there is the tiny amount of refrigerant that is lost at the point of connection / disconnection which over thousands of cars can add up to a lot, very bad for the planet as R-134a has a global warming potential of 1430.

As a member of the Institute of Refrigeration (Yes, really, there is one!), the whole automotive A/C service process is a hobby horse of mine (I know, I should get out more). There are “special” machines which only check for leaks by pulling a vacuum. This is wholly inadequate as it is a fraction of the operating pressure (even if the vacuum was perfect it would be 1 bar, working in the wrong direction, with the running pressure up to 20 bar) whereas it is legally mandated for fixed systems to pressure test to 1.2 x the MOP (maximum operating pressure).

In any event, the take away is as Matt says, if it ain’t broke, don’t fix it. If the system is well sealed, the refrigerant won’t react with anything, the filter won’t get saturated or blocked and all will be rosy. If it starts working badly, makes gurgling noises from the dash or stops completely then get it fixed. Oh, and run it often, as if the seals dry out then the above will start.
 

ChrisNico

Member
Messages
171
Thank you for this valuable info. I do hear more noise (slight hissing) from the vents when the A/C is active. Is this a sign that the A/C needs a service?
 

Zep

Moderator
Messages
9,110
Thank you for this valuable info. I do hear more noise (slight hissing) from the vents when the A/C is active. Is this a sign that the A/C needs a service?

Is it still cold? If you have a digital thermometer (most people have these days) it should be between 5 and 10 degrees C at the vent.

In any event, it is certainly not a leak as if you can hear a hiss then it would have stopped working already. Signs of shortness of gas is more like a gurgling noise from under the dash, this is what is known as flash gas forming in the liquid line, where the liquid boils before it reaches the metering device.
 

conaero

Forum Owner
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34,594
You have on the system both high and low pressure sensors.

If you don’t get a ‘click’ from the pump engaging then the system shuts off from the sensors.
 

midlifecrisis

Member
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16,102
Good answer Zep, so is there any truth in running the air con in winter to keep seals moist? Or is this another myth?
 

conaero

Forum Owner
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34,594
The usual failure on GT and QPV is the failure of the compressor nose bearing. You will hear a grinding coming through the ac when you turn it off or on.

you can also grab the clutch on the front of the compressor, engine off obviously and see if it has excessive movement.