Does my evaporator core REALLY need replacement?

I'm pretty handy, but I don't want to be dash-removal-handy. My AC isn't working and I want to try to fix it myself.

The shop quoted me $2k+ because, they say, the whole system, evaporator included, needs replacing. Their theory is the compressor is toast and sent metal through the lines, which they say means full system replacement (compressor, condenser, evap, expansion valve).

During their diagnosis they purged the system, repressurized and found no leaks. I haven't seen any leaks either and the system remains pressurized 2 months later, but AC light is still blinking. I thought that metal in the system would means leaks...

I don't want to unnecessarily replace the evaporator or expansion valve. It would mean removing almost the entire dash (hence the shop's labor cost). I just want to replace the compressor(w/ clutch), condenser, receiver/drier, etc which are easier jobs (after having the system purged at a shop).

Is there a way to tell if I absolutely need to replace the evaporator and the expansion valve? I've pulled the glove box and do not see any leaks at the evaporator location. I've read there is a desiccant bag on the condenser that would show if the refrigerant was excessively metallic.

 

If the compressor is bad that’s all you have to replace.

 

So if the compressor went bad. You could replace the compressor, definitely the condenser since the dryer is attached to it, expansion valve (which can be done from the out side) while the system is open they could do a thorough flushing of all the lines and the evaporator. They usually recommend replacing it all to cover their ass.

 

How could I tell if it's just the compressor? Can the supposed desiccant bag in the condenser be opened up to see what the oil/refrigerant looks like?

 

They sound timid and unsure, basically changing the whole fucking thing is nuts.

I would remove the compressor before saying its full of metal.

 

Would help to know what year your truck is.

You would have to dump the oil on the old compressor or pull the filter out of the condenser to check for metal contamination but if the compressor is locked up then odds are it does have metal contamination.

If there is metal contamination then at a minimum you need to replace the compressor, condenser, inline filter at the expansion valve, and flush all the lines & evaporator thoroughly. I would also recommend replacing the expansion valve, it can be accessed through the opening on the engine side of the firewall if your truck is an 05-15

https://www.tacomaworld.com/threads/a-c-filter-screen.482864/#post-24272716

 

No. You’d have to cut it open. You could run the flush through it and see what comes out. If the compressor is simply not coming on, there is a reason it’s not coming on or is it turning off after due to hi/low pressure?

 

This too^^. Need to know how they diagnosed it.

 

A/C light is flashing so that indicates the A/C Amplifier is commanding the compressor on but isn't seeing a signal from the compressor Lock Sensor. Need to determine if the clutch is engaging or not for the few seconds before the light starts flashing.

 

I thought the same thing. Reporting back to me that they've purged then pulled vacuume and confirmed lack of leaks doesn't have me confident the evap needs replacing.

I've read that thread almost compulsively. They insist that not only is there no filter at the expansion valve, but that the expansion valve CANNOT UNDER ANY CIRCUMSTANCES be removed from the firewall without full dash removal. They all but called me a careless redneck for even suggesting it. I'm not careless.

How do I get at the filter in the condenser? I have the FSM, but am not finding it.

Not sure how to flush the system at home. Is there some sort of non-refrigerant flushing material? Can have the Freon removed by a shop and have them tell me?

Truck is 2015 4x4 access cab. Edited to add: 126k miles and compressor is original as far as I know.

Clutch is good. I initially though it was the clutch, but after replacing the fuse, the clutch worked fine for a short while, before the fuse blew again. Edit to add: even with the clutch working, cold air was absent.

This is an amazing amount of quick help, cheers!

 

Word. They clearly wanted no part of it. Hell, if you want no part of it, just say that. Too many businesses/contractors these days giving the F-off price. Just level with me FFS.

 

Was this a dealer or private shop? From your last post I would not feel confident they know what they’re doing?

 

Did it just stop blowing cold and they told you that you need a compressor and complete system replacement?
Or, did you hear the compressor making a ton of noise and it finally stopped working with the A/C light flashing?

30 years in the automotive field and I never had to replace anything in a system because of compressor failure apart from the compressor itself.

 

Private shop. I don't see in the FSM that there's a filter either, so I guess I can't fully fault them...

It stopped blowing cold and I checked the simple stuff (clutch engagement, fuse, wiring to the clutch) and then took it in. They confirmed the system held pressure no leaks, but said Freon wasn't flowing. I didn't really hear anything that I identified as the compressor, but I'm terrible at diagnosing sound.

Consensus seems no evaporator replacement is needed. I would like to see if there's metal in the oil though and am wondering how best to do that.

 

Not sure, I haven't done one on a Tacoma yet myself but I know there are others that have changed it without pulling the dash.

That's because it's not a serviceable part according to Toyota (pretty much everyone changes the condenser anyway because it has to be removed to change the filter and desiccant bag), there's a plug at the bottom of it that contains a filter and the desiccant bag.

There's plenty solvent based flushes that are easily obtained at any parts store, some are pressurized in a can and others need a flush gun. In either case you need an air compressor and blow gun to blow it through and clear it out.

Yes you should have the refrigerant recovered by a shop, it's not technically legal to release it into the air.

Have you checked if only the rubber failed on the clutch or if the compressor is locked up?

 

That's interesting, we see a ton of compressor failures here. At least 2/3 of them have some kind of contamination (metal, "black death", or stop leak) and more than 25% of them fail catastrophically, we pretty much always replace the compressor and condenser at a minimum. Micro-channel condensers can't be flushed effectively so any sign of contamination it gets a condenser.

Most shops aren't gona put any kind of warranty on an A/C job unless the condenser, expansion device, and accumulator/filter drier are replaced with a new compressor. Some will insist on replacing the evaporator as well if there is contamination but that's usually not necessary as the metal filings typically don't make it past the condenser and expansion valve.

 

You would either need to pull the condenser and take the filter out or take the compressor off and pour the oil out (make sure to measure it though).

 

Agreed. Try to spin the compressor hub by hand atleast 10 turns non stop, not the belt pulley. It should have consistent resistance but be easily turnable by hand. If it's loosey goosey or stiffens up after a few turns then recover the system and pull the easiest line, closer to compressor discharge the better and check for metal filings or black sludge.

If it feels like then I would check your compressor lock sensor to make sure it's not "electrically" seized.

If you see any then I would also recommend replacing the condensor, drier(if applicable as a separate part) and txv along with the compressor.

Back flush the system with a flush gun filled with flushing compound. If flush compound isn't attainable then you can also get a small barrel or brake clean to fill the gun with. Just give it a minute to evaporate before reconnecting lines and add an extra 0.5 oz of oil to the total recommended system capacity as brake clean will strip ALL oil from the system without mercy. After than, pour the system oil into each component instead of leaving it all in the compressor (preferably), pull a good vacuum, charge it and go from there.

 

I will look into having a shop do the flush/recovery first. I knew I could add Freon from a can, but this is the first time I've heard of flushes too. Learn something every day. 10-4 on the legality and agreed, I've seen people get this work done without the dash removal. Where there's a will...

And many thanks for the info on the condenser filter. Like the condenser filter, I'm assuming the filter near the expansion valve is also not meant to be user serviceable since the service manual seems to ignore it completely.

I have not checked if the compressor is frozen, but would assume it would be on borrowed time if it were and I'd want to replace it anyway. Before the shop was involved I did see the compressor pulley spinning, both with (intact fuse) and without (broken fuse) the clutch being engaged. I assume that means the issue is internal to the compressor. Hoping things are glitter-free.

 

The repair warranty was their excuse for including the evaporator in the recommended work. I was just surprised when they didn't pull the compressor, but maybe that's outside the scope of the diagnostic...

Fantastic post and information. I'll take a look at the compressor hub tomorrow. I'll be ordering parts shortly.