Seized A/C Compressor

[abizzle]

Been a while since I last posted. My 2018 Sportback now has 121K miles and it left me stranded for the 4th time. This car has been a maintenance nightmare and has created a constant sucking sound emanating from my wallet!

My A/C compressor seized yesterday shortly after I left work and I ended up having to leave it overnight at a semi-shady gas station 15 miles from home. It started as a rough idle and quickly escalated to smoke coming from the right front wheel area. The smoke lasted maybe 40 seconds and then I received an alarm for the battery charging system. The temp gauge went full hot and I received an engine overheating alarm just as I pulled into the gas station.

I parked to the side and let it cool off without looking under the hood first. It started right up but the temp went full hot again, so that’s when I looked under the hood. I saw the serpentine belt hanging down so I pulled it out and shut the hood. I reserved any further diagnosis until after I changed the belt, which I completed about 1:00PM today.

As soon as the clutch engages, the car will shut off. I think it’s pretty apparent the compressor needs to be replaced and the system will need to be evacuated and recharged. It may need to be flushed too. A new compressor is $250 and a system charge is $300. I don’t know how much extra it would be to evacuate the system and/or flush it. I would really like to find a heavy-duty compressor that fits my car. What do they use in police cruisers? They sit for long periods of time with the A/C running.

Yeah, these $500 and $600 repairs are getting really annoying.

 

[Gub]

Been a while since I last posted. My 2018 Sportback now has 121K miles and it left me stranded for the 4th time. This car has been a maintenance nightmare and has created a constant sucking sound emanating from my wallet!

My A/C compressor seized yesterday shortly after I left work and I ended up having to leave it overnight at a semi-shady gas station 15 miles from home. It started as a rough idle and quickly escalated to smoke coming from the right front wheel area. The smoke lasted maybe 40 seconds and then I received an alarm for the battery charging system. The temp gauge went full hot and I received an engine overheating alarm just as I pulled into the gas station.

I parked to the side and let it cool off without looking under the hood first. It started right up but the temp went full hot again, so that’s when I looked under the hood. I saw the serpentine belt hanging down so I pulled it out and shut the hood. I reserved any further diagnosis until after I changed the belt, which I completed about 1:00PM today.

As soon as the clutch engages, the car will shut off. I think it’s pretty apparent the compressor needs to be replaced and the system will need to be evacuated and recharged. It may need to be flushed too. A new compressor is $250 and a system charge is $300. I don’t know how much extra it would be to evacuate the system and/or flush it. I would really like to find a heavy-duty compressor that fits my car. What do they use in police cruisers? They sit for long periods of time with the A/C running.

Yeah, these $500 and $600 repairs are getting really annoying.

Ugh. Sorry to hear about the issues. I hope you can get it fixed quick and on budget but.... you might want to think about cutting your losses now. Sorry to say but the parts supply issues and tariffs etc. means this vehicle aging will probably not go well. Keep us posted on your findings.

 

[afalco]

Mind sharing the easiest way to gain access to change the serpentine belt.

 

[HotZ28]

What engine do you have?

 

[afalco]

What engine do you have?

2018 TourX 4cyl. Thanks in advance

 

[abizzle]

Mind sharing the easiest way to gain access to change the serpentine belt.

Now that I’ve changed it twice in less than a week, I can tell you that removing the RF tire and motor mount is not necessary. We did that the first time. You absolutely need the specialty tool for the tensioner, which can either be rented or you can buy a cheap one at Harbor Freight.

The second time, we routed the belt around everything but the crankshaft pulley, released the tension and slipped it on. I don’t see how it can be done by one person. I would also recommend jacking up the RF and putting a jack stand in place. Ain’t much room under there without it.

 

[abizzle]

What engine do you have?

The 2.0L LTG engine

 

[abizzle]

I ended up buying a used AC Compressor through LKQ for about $250 and it will be here tomorrow. The donor vehicle was a 2021 Blazer. My original plan was to replace the compressor and then take the car to the shop to have the system charged. I'm now thinking it may not be that simple.

Is there anyone with HVAC experience that can offer some suggestions? I'd like to do as much of the work myself as possible, but I'm not interested in buying a set of gauges or a vacuum pump or a flush gun. Can I just replace the compressor and let the shop do the rest?

As a side note, once this repair is complete, I will have spent between $1500 and $2000 on the AC system in the last year. I lucked up and found a shop to charge the system for $300. Three other shops in town all wanted $600, which is like highway robbery on a dirt road!

 

[abizzle]

After five long weeks of driving with no A/C in the oppresive South Louisiana heat and humidity, I am finally ready to begin repairs. You see, I had been out of work for a full year and the compressor decided to fail only three days after starting my new job. As you can imagine, I had several financial obligations requiring immediate attention, so the A/C got pushed to the bottom of the list. On a positive note, it gave me plenty of time to study and determine exactly what needed to be done.

My initial plan was to replace the compressor myself and then pay a shop to evacuate, flush, and charge the system. Then I realized there are several more parts that need to be replaced, including the condenser. Once I drain the oil out of the old compressor, I can determine the level of contamination in the system, if any. I'll take it to the shop and have them evacuate the system and I should be able to handle the rest, including charging the system.

Parts List

Compressor (Used from a 2020 Chevy Blazer with 27K miles on it) = $243.64
Kool Vue 37BC23Y A/C Condenser = $67.53
A/C Expansion Valve = $11.17
A/C Refrigerant Pressure Switch $16.87
A/C Refrigerant Temperature Sensor (13276269) = $22.61
GM O-Ring and Sealing Washers Kit = $9.83
A/C PAG 46 Refrigerant Oil = $11.68
4-way Manifold Gauge Set for 1234yf Refrigerant = $82.99
1/3HP 4.5cfm HVAC Single Stage Vacuum Pump = $71.99
Honeywell R-1234yf Solstice Refrigerant 8oz. (3 cans) = $80.00

Total Parts = $618.31

 

[abizzle]

This is turning into quite a project. I went to a local shop to find out how much they would charge to evacuate my system and the guy quoted me $80.00. That's not terrible, but when I told him the freon is most likely contaminated he said his machine would not recover contaminated freon. He said it has a special mechanism that will shut the machine off if it detects contamination. When I asked him how I was supposed to get the freon out, he tells me to discharge it into the air.

Then I found the following GM Service Bulletin:
GM Service Bulletin 12-01-37-001F

So, the moral of the story is... if you plan to "legally" work on your own A/C in the future, prepare to buy about $20K in specialized equipment and become an ASE certified mechanic. Otherwise, prepare to shell out a minimum of $1,200.00 at your local A/C service center. I don't even want to know how much a dealer would charge for doing this work outside of warranty.

As for me and this particular project, I'm going to do what they guy at the shop told me to do. I'm too far into this project for anything else.

 

[gprcomputer]

Hey just FYI, I just installed an aftermarket "Kool Vue" condenser into an HHR this past weekend, I had to use it as it's what I had on hand and nothing was available locally. It was an elderly family member's car so the AC HAD to be working ASAP but I'm not real happy with the Kool Vue condenser. It fit real well actually, no problems there and it even didn't leak any AND the AC is working well enough it seems so far and it's been hot BUT I did notice some things during install and I checked into them online and this video explains everything perfectly.

The Kool Vue had 38 rows compared to OEM's 44 on my HHR install and I'll bet many of them are this way as pointed out in the video. I already knew the subcooling takes place in the last few rows which is why I was concerned about there only being 38 vs 44 and sure enough when checking online, there was a video about just that very thing.

I know there's usually a huge cost difference and it's what made me go for the Kool-Vue on the HHR but you might want to consider something a little better for your condenser.

 

[abizzle]

Hey just FYI, I just installed an aftermarket "Kool Vue" condenser into an HHR this past weekend, I had to use it as it's what I had on hand and nothing was available locally. It was an elderly family member's car so the AC HAD to be working ASAP but I'm not real happy with the Kool Vue condenser. It fit real well actually, no problems there and it even didn't leak any AND the AC is working well enough it seems so far and it's been hot BUT I did notice some things during install and I checked into them online and this video explains everything perfectly.


The Kool Vue had 38 rows compared to OEM's 44 on my HHR install and I'll bet many of them are this way as pointed out in the video. I already knew the subcooling takes place in the last few rows which is why I was concerned about there only being 38 vs 44 and sure enough when checking online, there was a video about just that very thing.

I know there's usually a huge cost difference and it's what made me go for the Kool-Vue on the HHR but you might want to consider something a little better for your condenser.

That's good info and I appreciate you taking the time to research and post it. Had I known that before buying the Kool Vue, I may have opted to pay the additional $125.00 for an OEM condenser. This is actually my second condenser replacement in about a year. I purchased a TYC brand last year simply because it was the recommended "value" replacement from Rock Auto. It has worked just fine and the only reason I'm replacing it is because it cannot be flushed, which also applies to the OEM.

 

[abizzle]

Just posting an update and I wanted to note that I didn't deliberately release the freon into the air. I started to, but when I depressed the Schrader valve it barely let out a wisp, which obviously means there's none left in the system and it leaked out at some point. I'm fairly confident the system is intact and the freon was released when the compressor locked up or it has slowly leaked out over the eight weeks since it happened. Up until then, it had been cooling well and I had no issues. I'll know for sure when I pull a vacuum on the system.

I'm having to rely heavily on the Service Manual to do this job because I have no previous experience working on car AC systems. It can be a challenge because the manual skips around a lot. For example, there's not one single procedure for replacing the compressor. It's a combination of several other procedures that are scattered throughout the manual and some specific things related to the compressor. There is also a severe lack of Internet content available for R-1234yf systems. Hell, Four Seasons still hasn't updated their documentation to include 2018+ Regals.

I wasn't able to measure the amount of PAG oil in the system because there was none in the old compressor. The manual says the approximate PAG Oil capacity in the compressor is 2.03 oz., so that's what I put in the replacement compressor before installing it last night. I still have to torque the bolts before moving on to flushing, vacuuming, and charging. Luckily, I found a video showing how to use the old Expansion Valve to flush the evaporator and all the lines at one time. That will save a lot of time and energy!

I'll try to post some pics later today.

 

[gprcomputer]

Hey, I'm well versed in auto AC and residential hvac for that matter. I haven't worked on a 1234yf system yet, the Buick is my only vehicle with it but I bought all the adapters and things for future use but I digress.

This quote worries me, "The manual says the approximate PAG Oil capacity in the compressor is 2.03 Oz" - I believe that would be correct if you're JUST replacing the compressor but generally, automotive AC systems have an oil capacity around 8 ounces but of course that varies some based on make, etc.

As a general rule, when you're replacing the whole system you would do something like... 2oz in the compressor, 2oz in condenser, 2oz in the evap. And 2oz in the receiver. I'm almost certain 2oz for a whole system is way too low and you'd end up with another burnt compressor.

That's calling on my experience from 134a systems, maybe 1234yf systems are 'that' drastically different? But I didn't think so.

Good luck though!

 

[abizzle]

Hey, I'm well versed in auto AC and residential hvac for that matter. I haven't worked on a 1234yf system yet, the Buick is my only vehicle with it but I bought all the adapters and things for future use but I digress.

This quote worries me, "The manual says the approximate PAG Oil capacity in the compressor is 2.03 Oz" - I believe that would be correct if you're JUST replacing the compressor but generally, automotive AC systems have an oil capacity around 8 ounces but of course that varies some based on make, etc.

As a general rule, when you're replacing the whole system you would do something like... 2oz in the compressor, 2oz in condenser, 2oz in the evap. And 2oz in the receiver. I'm almost certain 2oz for a whole system is way too low and you'd end up with another burnt compressor.

That's calling on my experience from 134a systems, maybe 1234yf systems are 'that' drastically different? But I didn't think so.

Good luck though!

Well, I'm quickly becoming well-versed because this project has been a nightmare. I just reinstalled the compressor for the fourth and last time and torqued all the bolts to spec. I had to drop it one last time to get the AC line reattached. So, as it stands, I have replaced the compressor, condenser, and pressure sensor, and I've removed, flushed and reinstalled the AC line between the compressor and condenser.

I pulled the old expansion valve and drilled it out, so it could be used to flush through the lines and evaporator in one step. Problem is, I can't seem to get the expansion valve reinstalled from the engine compartment and I'm faced with possibly having to perform a 48-step procedure to service the evaporator from inside the cabin. Just can't seem to get the valve fitted over both lines and then get a mounting screw threaded. I could flush the evaporator separately, but I'll still need to get the new expansion valve installed afterwards. Ugh!

I purchased the official GM flushing kit for $80.00 on eBay and it will be delivered by Tuesday, but this doesn't necessarily help. The expansion valve is the only thing standing in the way of me finishing this project.

I am also skeptical of the amount of PAG oil required for the entire system. I've been through the service manual several times and I haven't found any other information. The sticker under the hood only lists the amount of refrigerant (0.55kg or 19.87oz) and it calls out several SAE standards covering service requirements for this vehicle. I need to get a definitive answer on this subject and I can add the remaining oil through the service line.

I've posted a pic of the compressor and the sticker under the hood.

 

[abizzle]

Also, the RockAuto page for the OEM compressor says it comes with 3oz. of OE-specified oil...

More Information for GM GENUINE 86792446

 

[abizzle]

08/11/2025 Update...

The compressor and condenser have been replaced and reinstalled and I have the A/C line between the two components connected. The line is connected to the condenser and compressor, and the other end, while disconnected, is sealed to avoid contamination. The line connecting to the evaporator is also disconnected and the expansion valve is removed. I was able to reassemble the front end and get the car back on the ground last night. It started right up and not surprising, the check engine light came on.

The car seems to run a bit smoother, which is probably due to having good bearings on the compressor pulley. My electric fans, which were coming on way too often and staying on way too long, came on for 3 seconds this morning and shut off. I changed out the antifreeze yesterday and it's possible the system could have been a little low or the cooling properties of the OEM antifreeze had been diminished.

It is apparent that the evaporator and expansion valve should be serviced from the cabin rather than the engine compartment. In fact, you can order the evaporator kit and it comes with the expansion valve pre-installed. I wasn't planning on changing it, but since I've gotta go into the blower housing anyway, I'm going to swap the evaporator. I still intend to flush the system through the old evaporator because it's just easier than doing each line separately, but it works out better because I can monitor the flushing process to ensure nothing leaks in the cabin. Overall, I feel better about the remaining work because I know for sure it can be completed. There's no telling how much more time could have been wasted trying to service the evaporator from the engine compartment.

More to come...

 

[abizzle]

I called a local Buick stealer and inquired about the total amount of PAG Oil in the A/C system. I ultimately got to the Service Manager and he had to check with his technicians and call me back. None of them could provide a definitive amount, so this is what they recommended:

Total System Capacity: 4.03 oz.

1.0 oz. in the Condenser
1.0 oz in the Evaporator
2.03 oz. in the Compressor

I'm still not convinced that's correct because I know a new OEM compressor comes pre-filled with 3.0 oz, but it's acceptable for now. I will continue to seek a definitive answer and if the system needs more PAG Oil, I can add it through the service port. I'm assuming most people are going to let the stealership or a local shop make the repairs, but this will be an issue for anyone making DIY repairs.

 

[abizzle]

This is the most difficult maintenance project I’ve ever done. The attached pic was taken after the blower/evaporator enclosure was removed. I’m waiting on a new evaporator.

 

[abizzle]

Finally, I’ve started reassembling the interior and I’m gonna charge the system sometime today. I pulled a vacuum for 12 hours and it held just fine, so there are no leaks. I need to add 2 oz. of PAG oil and some dye through the service port before adding Freon.

This project kicked my @$$!