Possible AC issues on the Corolla

[jsean]

Noticed sporadic issue with the AC on the ‘05 Corolla over the last 2 days. Today was by far the worst on the drive home.
Started the car after work, AC felt weak. About 15 mins of stop and go/ slow driving (never maxing past 40mph), AC progressively got warm. Compressor and cooling fan running the whole time.
Stopped at the store on the way home - kept the car on remote start in the hopes it’d cool down some. I came out in about 10 mins - and it was blowing warm air out of the vents. Checked the compressor and cooling fan - running constant (no short cycling).
Turned the car off and let it sit for a min or two. Restarted the car, AC turned to max and it was a bit weak but cooling some. Ok weird..

Got home and measured 55psi on the low side which is about right apparently for the 95F day.

So what gives? I tried using the black light and can’t find any leaks. Last time the system was touched was about 30k miles ago when I changed out the condenser due to road debris (system was vaccumed, leak checked and refilled with UV dye).

Compressor is running constant and not short cycling. Any thoughts on how to trouble shoot this?
I noticed that when I turn on the AC button - the cooling fan kicks on, followed by a noticeable delay for the AC clutch to engage. The clutch seems a bit eccentric when it rotates but that could just be me imagining things.

Video link here showing AC compressor and what not (with audio):
AC compressor clutch engage/disengage

 

[Rand]

whats the intake and discharge temperatures?

 

[jsean]

How do I find the intake temperature? I’ll measure the discharge temperature tomorrow. At its worst today, there warm air blowing out of the vents - essentially no difference with the ac button on or off.

 

[clinebarger]

55psi isn't great, You need to know what the high side is doing.

 

[zzyzzx]

Car AC never works particularly good at idle when it's a 100 degrees outside.

 

[panthermike]

I'm not well versed in A/C diagnosis and repair. However, I sold my '03 Corolla to my buddy 11-12 years ago and for the last 2 years he owned it; the A/C would only blow warm with the occasional cool air. Someone told him compressor was bad. Last July, I bought the car back from him and the first thing I did (still at his house) was replace the A/C relay switch under the hood. When I left his house, it was blowing cold and has remained great for the last year.

Not saying that's your issue, but for $15 or so, may be worth a try. The one I purchased was Denso 5670001. Some Toyotas are known for the relay going bad and people spending too much money to fix it.

 

[We're Metals]

Compressor Clutch (not compressor but the clutch).

 

[repairman54]

Old car, measure the air gap on the compressor clutch. I've pulled a shim on a few worn ones and kept them going for a while.
They can be fine at idle and slip when the revs are up driving.

 

[We're Metals]

Old car, measure the air gap on the compressor clutch. I've pulled a shim on a few worn ones and kept them going for a while.
They can be fine at idle and slip when the revs are up driving.

Hard to wrap my feeble mind around it but at least in the Honda world, they can slip when you're at an idle at a light then regain grip again and function as normal underway. As @repairman54 said, taking out a shim will work for awhile (or perhaps indefinitely) but there is likely still metal on metal contact.

On a Honda Civic I changed the A/C clutch out at 204,000 miles, the A/C functioned normal when the car was cold or underway (highway) but warmed up at stoplights. Once I changed the part, I realized how **** noisy the clutch was. Its so much quieter. I was adding freon and messing around with that for ages, ended up being a not so common to the rest of the car world repair of the clutch.

 

[willbur]

Car AC never works particularly good at idle when it's a 100 degrees outside.

this corolla ac system was kinda weak even when new

 

[zzyzzx]

I'm not well versed in A/C diagnosis and repair. However, I sold my '03 Corolla to my buddy 11-12 years ago and for the last 2 years he owned it; the A/C would only blow warm with the occasional cool air. Someone told him compressor was bad. Last July, I bought the car back from him and the first thing I did (still at his house) was replace the A/C relay switch under the hood. When I left his house, it was blowing cold and has remained great for the last year.

Not saying that's your issue, but for $15 or so, may be worth a try. The one I purchased was Denso 5670001. Some Toyotas are known for the relay going bad and people spending too much money to fix it.

Relays are easily bench tested.

 

[panthermike]

this corolla ac system was kinda weak even when new

On my '03, I feel as though it is better than some newer systems! Some of the recent newer vehicles I've driven have not been impressive. Our CX-9 does ok, but falls flat when temps rise above 105 here.

 

[Chris142]

Is the suction line cold?

 

[Chris142]

this corolla ac system was kinda weak even when new

That's very uncommon for a Toyota.

 

[Rand]

the 2020 elantra is colder than my 24 outback.
the outback is fine.. but if you have it out in a 90f day after being parked in the sun it takes 10min to get going(longer if idling)
but it might just be less glass, and less interior to cool down helps the elantra too.

its definitely quicker to cool off after a heatsoak in the sun.

on a longer trip both are quite adequate.. had the outback in cleveland tues with 100f+ ground level temps.... was just brutal.. could have used twice the cooling for the first 15-20min after leaving the hospital.

 

[jsean]

55psi isn't great, You need to know what the high side is doing.

AC ran nice and cold today, go figure. Today was a 90F day vs. 100+ we’ve had the last 2 days when it was acting up.

With that being said, here are the reading I have:
1. Engine off

2. Idle (blower on max, recirc on)

3. Engine revving at 2k rpm (blower on max, recirc on)

AC vent temp is around 50-53F at idle. It cools down to about 43F while driving.

 

[jsean]

Car AC never works particularly good at idle when it's a 100 degrees outside.

It struggled to give much in the way of cool air even while driving when it was 100F+. Yesterday for a while, it was just warm air from the vents even with the ac on and compressor / cooling fan running.

 

[jsean]

I'm not well versed in A/C diagnosis and repair. However, I sold my '03 Corolla to my buddy 11-12 years ago and for the last 2 years he owned it; the A/C would only blow warm with the occasional cool air. Someone told him compressor was bad. Last July, I bought the car back from him and the first thing I did (still at his house) was replace the A/C relay switch under the hood. When I left his house, it was blowing cold and has remained great for the last year.

Not saying that's your issue, but for $15 or so, may be worth a try. The one I purchased was Denso 5670001. Some Toyotas are known for the relay going bad and people spending too much money to fix it.

This is a good point, I swapped the relay out with a spare one from the junkyard I had sitting around. No difference.

Of course, it’s down to 90F today and the AC was great while driving back from work

 

[jsean]

Compressor Clutch (not compressor but the clutch).

This is what I’m thinking it is. I can’t quite tell if there’s a bit of wobble on the clutch when it’s engaged. I can sorta kinda hear the clutch when it engages instead of the usual roar of the cooling fan.

How freely are the clutches supposed to rotate when the engine is off? It takes me quite a bit of effort to get it to move with the engine off…

 

[jsean]

this corolla ac system was kinda weak even when new

The ac on this thing has always been great. Never topped off or touched the AC system until 2 years ago when gravel from a dump truck took out the condenser. After the fix, AC has always been nice and cold except the past 2 days.