# 2014 2.0l L4 TD R-134a cooling system problems a/c AC air conditioner



## Snipesy (Dec 7, 2015)

Uhhh what are you measuring first off? More importantly how are you measuring? With what? Yes those are a bit high but Occam’s razor.

As for what is normal.... 1.4lbs or whatever is on the sticker. I do not believe GM publishes the performance data at least I’ve never seen it. You can find generic humidity,temp,pressure charts online and those are generally “close enough”.


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## LeBail (Aug 6, 2020)

Tested the low side pressure using a redtek AC charger gauge/ hose.


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## Snipesy (Dec 7, 2015)

LeBail said:


> Tested the low side pressure using a redtek AC charger gauge/ hose.


Well the recharge kits aren't exactly known for their robust gauges.

But its likely overfilled and you have to take it to a shop.


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## snowwy66 (Nov 5, 2017)

There is no particular normal for any specific car. They all have the same pressure. 

What none of you realize. Is car needs to be at 2000 rpm. When checking pressures. Not idle.

Your car spends 95% of its life driving down the road.

Ac off. 115 equalized is about normal. Fully charged.

80 when running is too high. Weak compressor.

35ish LOW is normal for all cars. 250 - 275ish HIGH. 2000 rpms


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## pandrad61 (Jul 8, 2015)

Side note you could remove the air block off plates in the upper grill to allow more air in. More airflow through condenser in theory should shed heat more efficiently and thus cooler in cab.


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## jblackburn (Apr 14, 2012)

Did you add R134a to the system? If you did, it's probably drastically overcharged now.

You need both high and low pressure numbers to diagnose what's going on with one of these variable displacement compressor setups.


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## LeBail (Aug 6, 2020)

jblackburn said:


> Did you add R134a to the system? If you did, it's probably drastically overcharged now.
> 
> You need both high and low pressure numbers to diagnose what's going on with one of these variable displacement compressor setups.


Thanks for all the Replys guys, I did however test the system for the ON portion at 2000RPM using my Fathers extra foot, and to run the AC, because I read on another topic here that the AC works differently at idle in new cars(?) and wanted to rule that out if true.

This all stemmed from me thinking it was just low and realising it was so high before I put the bottle I had bought in, so it's possible the last owner over charged...
I'm going to figure out my high side pressure now before anything else, even it it means buying a manifold.


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## pandrad61 (Jul 8, 2015)

LeBail said:


> Thanks for all the Replys guys, I did however test the system for the ON portion at 2000RPM using my Fathers extra foot, and to run the AC, because I read on another topic here that the AC works differently at idle in new cars(?) and wanted to rule that out if true.
> 
> This all stemmed from me thinking it was just low and realising it was so high before I put the bottle I had bought in, so it's possible the last owner over charged...
> I'm going to figure out my high side pressure now before anything else, even it it means buying a manifold.


Harbor freight has some nice ones for a very good price. Should do the job well and not cost a fortune.


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## snowwy66 (Nov 5, 2017)

Most cars are somewhat worthless at idle.

The engine idles at 750 rpm.
Most cars don't have radiator fans operating untill the high preasure gets high enough to kick it on. Somewhere around the 325ish psi range.

Driving down the road. You've got good engine speed and air flow through the condenser. No radiator fan needed. Unless you're in Iraq where it's 130 year round.


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## snowwy66 (Nov 5, 2017)

pandrad61 said:


> Harbor freight has some nice ones for a very good price. Should do the job well and not cost a fortune.


That's where I get my gauges. $60 normally. I wait for a sale.


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## LeBail (Aug 6, 2020)

I bought a set off Amazon that can do the 4 main refridgerants, should be here Monday. specailty parts always seem to be more money in Canada.
I feel it's going to be a weak compressor.


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## LeBail (Aug 6, 2020)

After getting my gauges in its apparent the compressor only puts any pressure to the high side when drving at high RPMs, abeit very slowly, explains why it was working on the highway but not in the driveway. I had thought it may be the fan was not kicking on but after going through a maze of confusion I realised my vehicle was made with 5 cooler fan relays that do absolutely nothing and shouldn't be there because the fan is controlled by the cooler fan module which in turn is controlled by ECM via PWM ( pulse-width modulation) signals. so Likely problem being the compressor i'm now in the works of finding the cheapest one in Canada, which seems to be 350$ online or 730$ at NAPA, yikes.


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## pandrad61 (Jul 8, 2015)

LeBail said:


> After getting my gauges in its apparent the compressor only puts any pressure to the high side when drving at high RPMs, abeit very slowly, explains why it was working on the highway but not in the driveway. I had thought it may be the fan was not kicking on but after going through a maze of confusion I realised my vehicle was made with 5 cooler fan relays that do absolutely nothing and shouldn't be there because the fan is controlled by the cooler fan module which in turn is controlled by ECM via PWM ( pulse-width modulation) signals. so Likely problem being the compressor i'm now in the works of finding the cheapest one in Canada, which seems to be 350$ online or 730$ at NAPA, yikes.


So factory did all those redundant relays? Odd


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## jblackburn (Apr 14, 2012)

LeBail said:


> After getting my gauges in its apparent the compressor only puts any pressure to the high side when drving at high RPMs, abeit very slowly, explains why it was working on the highway but not in the driveway. I had thought it may be the fan was not kicking on but after going through a maze of confusion I realised my vehicle was made with 5 cooler fan relays that do absolutely nothing and shouldn't be there because the fan is controlled by the cooler fan module which in turn is controlled by ECM via PWM ( pulse-width modulation) signals. so Likely problem being the compressor i'm now in the works of finding the cheapest one in Canada, which seems to be 350$ online or 730$ at NAPA, yikes.


Similar behavior from my 2012 turned out to be a faulty/clogged expansion valve. The compressor then failed <6 months later though.


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## LeBail (Aug 6, 2020)

jblackburn said:


> Similar behavior from my 2012 turned out to be a faulty/clogged expansion valve. The compressor then failed <6 months later though.


Was it ever able to get low on the low side? Mine will not get low enough, ever but I will probably replace the valve while I'm at it. Do you know if any other vehicles have this same compressor or is it proprietary?


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## jblackburn (Apr 14, 2012)

LeBail said:


> Was it ever able to get low on the low side? Mine will not get low enough, ever but I will probably replace the valve while I'm at it. Do you know if any other vehicles have this same compressor or is it proprietary?


No; most of the time it wouldn't even run at idle in 90+ weather because high side pressure was too high until there was more airflow through the front. When it did run (lower ambient temps), the fan at the front of the car was SCREAMING.

Looking at a parts website, the Diesel does look to use a different compressor than the 1.4/1.8. Not sure who makes that one.


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## snowwy66 (Nov 5, 2017)

A low low and high high would be the valve. It acts like a blockage and can actually create a vacuum on the low side if it gets bad enough. 

My semi did that 2 years ago. 

A hi low and low high would be weak compressor. It's not pumping full flow.


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