AC blowing very inconsistent Is my compressor clutch going?

Good afternoon all, this isn't technically my first post. I was a member for quite some time but haven't been active since 2013, I guess my account was deactivated. So, I understand the search function and tried.

Anywho, when I get in the truck and start the truck, my AC blows hard and cold and seems to be in good working order. After some time on the road (usually around 20-30 minutes), I notice it blows significantly weaker on all settings, and icy cold condensation starts to come out like smoke from the vents. It will do this for about 10 minutes the blow kind of cold. The AC won't start blowing hard again unless I don't run the truck for some time. Does anyone have any ideas on what it could be, or where to start trouble shooting?

This is good timing I suppose, because my power steering rack just started dumping oil and will have to be swapped. I'm going to do all the work myself and want to do it all at once if it's the compressor.

 

When you say it blows weaker, you talking air speed/volume out the vents, or temperature?

I'm guessing the former, and from your description it rather sounds like your evaporator is icing up, which can be caused by a few things... one of them is not having enough air moving over the evaporator coil. Which can be caused by a cabin filter all clogged full of crap. How's your cabin filter looking?

 

Just changed the cabin air filter, it was atrocious.

The speed and volume slows down after about 20/30 mins then it starts blowing warmer air about 10 minutes after.

 

Air speed and volume don't have anything to do with the A/C system itself, per se. The blower motor is its own thing, it can cause A/C issues (like a frozen coil) but not the other way around.

Blowing warmer could be related if the blower cutting out is letting the coil freeze. Or you could have multiple issues... pretty likely from the sounds of it.

Checking the connectors on the blower motor itself, and the resistor that controls the lower speeds, would be a good start. The HVAC airbox is made by Delphi just like GM, and they brought along their propensity to melt connections!

 

Is the blower motor located in the glove box with the cabin air filter?

 

Just replaced fan blower on wife's crv this weekend, was blowing intermittently as you described. Bought a cheaper replacement off Amazon, works great now.

I think a clogged cabin air filter contributes to the fan going out as was mentioned, hers was awful.

Usually are located under the cabin air filter below the glove box. Easy repair if that's the issue.

 

Blower motor is underneath, right above the passenger footwell. I believe the resistor is right above it, but I'm not 100% on that off the top of my head, haven't had to mess with mine.

 

This is not a blower or filter issue.

Your evap is freezing up. This stops airflow and creates the 'fog' at the vents just before happening.

After it thaws out (when sitting) it works fine the next use.

There is a thermistor that is supposed to prevent this from happening by cycling the compressor when the evap gets to about 38 or so.

Likely that has failed. Inexpensive part in most cases, but I don't know how tough it is to get to in the Tacoma.

@koditten is replacing this thermistor something you have experience with? Location and access?

 

I have a 2010 and noticed that it wasn't blowing as cold as it should have been on our last road desert road trip. I change the cabin filter every 6 months and decided it was time to suck it up and take it in to the shop. I don't like the junk cans with gauge and I'm willing to pay to have it done correctly. As I suspected after 9 years it was a little low on charge and cost me $121 to get it blowing right. I've had friends really screw up with the junk cans so it was a no brainer for me.

 

Clearwater Bill is probably the most correct of all the suggestions above. I had the same symptoms ( Ice and Fog out of the vents and a slowing of air flow ) on an old Camry Wagon my wife owned. Had the dealer replace the Thermistor and all was well for over another 150K miles when she sold it.

 

This actually makes the most sense.

I get a smell out of it, it's not a rubber or mechanical. It smells like moisture. Does that indicate anything?

 

I'll bet a whole week of my lunchtime Diet Coke that's what it is.

As far as the smell, it's possible your condensate tube is at least partially clogged, since you mentioned your filter was overloaded. A shop vac on the firewall drain line might help with that, and an AC refresh kit in the evap case should kill off the mold.

Something like this https://www.zep.com/product/zepcorporate/a-c-refresher-kit

Not recommending that product, just the type of product. And there is no reason to pay 2x for a can labled 'Toyota'.

And your condensate is not being produced normally. You're building up a block of ice (literally) and then it all melts and fills the case, along with whatever debris is in there.

 

I seriously hate to admit this, but I didn't change my cabin air filter for 110k miles. So there's that. I'm sure it made the system run a lot harder than it should've. The filter looked terrible.

 

I would've liked to have seen how bad that filter was! Jeez. 110k ....Mine is dirty after 10!

 

Unscientific way to check the thermistor. Drive until you get the conditions you described. Turn the AC off but leave the fan on high. Drive 5 more minutes then turn the AC back on. Work more better? If yes, bad thermistor.
Edit: no it's not your ac clutch.

 

You're welcome lol.

 

Just got mine in the shop after AC started becoming intermittent and then finally gave out completely. It turned out the Blower Motor melted and the connector melted as well. Had to replace entire part and electrical.