AC blows less-cold at idle/standstill, ice cold while moving

[SZR48207]

I think this is just a design flaw on my 2015 Tacoma but maybe you folks can toss some ideas my way.

As the title states, if I'm sitting at a light or parked, the AC blows "cool" but it usually isn't cold enough to keep up when temps outside are 95+. Once I get moving, it blows plenty cold.

I guess it's just an airflow issue with the condenser? I have not had an A/C shop check the charge level since the system can blow cold enough at the right speeds, so I assume the charge level is correct.

Could I add supplemental electric fans or anything to assist with moving the hot air out from the engine bay?

 

[mclasser]

My Accord was like that; it just needed a slight top off after 15 yrs.

Of course, you wanna first check the basics like dirty condenser, dirty cabin filter, spinning rad fans, etc.

 

[A_Spruce]

I agree. I suspect the system is slightly low, as "not as cold as it should be" is typical of a system that is low on refrigerant. You don't necessarily have a leak, systems naturally lose charge over time. When you have it serviced, they should perform a dye check for leaks before refilling system. Many shops run AC specials where they don't charge an inspection fee to test your system. Worth a look if you don't have a regular shop.

 

[928]

If it if full (check with gauges) it's the joys of having r134- the car at the light doesn't get enough airflow through the condensor

 

[demarpaint]

I'd make sure the condenser is clean, and the fans are operating properly, then put gauges on it and see if it needs to be topped up. In extremely hot weather I always found AC, even in a perfect system to perform slightly better when the car is moving vs. sitting in traffic with very little air flow through the condenser.

 

[vwmaniaman]

At idle your compressor is turning slower so capacity of coolant flow is less.

 

[Delta]

My 2009 Tacoma 4.0 V6 is the same way. These trucks do not have an electric fan and rely on the clutch fan to do all the work. Not as much airflow going through there at idle. If you can find a spot for an electric fan, good luck, there's not much room under there for anything...

 

[Amkeer]

Check your fan clutch. If its not working correctly temperatures will rise.

 

[Saabist]

My car started exhibiting the same symptoms when the condenser fan stopped working. The AC is fine until outside temperatures go above the low 90s, especially on sunny days, then it gets pretty marginal at stop lights. One of these days I'll have to get around to replacing the fan (I already have the part), but it's a PITA job because a lot of crap has to be taken apart and there's not much room to work.

 

[Jake_J]

That's pretty much normal behavior, you're compressor is doing more work while driving at 2,000 rpm versus idling at 650 rpm so the A/C blows colder when moving.

 

[MCompact]

I had that happen to my 2er; I suspected the auxiliary fan and I was correct- it was replaced under warranty.

 

[zzyzzx]

This is pretty normal behavior, even more so with stop start technology.

 

[john_pifer]

Surprised at that. My 2007 Tacoma is always ice-cold, and it's never been recharged.

Does great even with Tennessee summers.

Of course, it does cool off faster after the truck has been sitting, when I'm moving. But I never notice it warming up at traffic lights.

 

[bulwnkl]

At idle your compressor is turning slower so capacity of coolant flow is less.

That is not the reason. The reason is that the condenser does not reject as much heat when airflow across it is low. The fan(s) move(s) a whole lot less air across the condenser than driving down the road does.

 

[Yah-Tah-Hey]

That is not the reason. The reason is that the condenser does not reject as much heat when airflow across it is low. The fan(s) move(s) a whole lot less air across the condenser than driving down the road does.

Right in Bul, that is what I was about to post.