Where are you on this? MIke
Out of options for cold AC -- I'm spent.
- Thread starter Pskhaat
- Start date
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My 91 converted to the current freon blows ice cold in 100* temps
when it is not blowing cold air is the compressor clutch running? My other car I had to replace the A/C relay for the same type problem.
when it is not blowing cold air is the compressor clutch running? My other car I had to replace the A/C relay for the same type problem.
Get a thermometer, stick it in the vents, and read the temp. Turn your AC on full blast and idle for a while and see what the temps do. Then drive around, and see what the temps do. The report back.
Until you get us more data, we can't help you.
x2, check the vent temps. I just boosted my fan clutch to 20k. I'm now getting vent temp of 55 to 60 at idle. Unboosted, I was doing good to keep it below 80 on a hot day. A dark truck sitting in the sun at 115 will be 150 inside at start up. Even with good a/c it takes a long time to cool it down
.It still sounds like its not working correctly. Did a shop charge the system or did you? 134 systems are very sensitive to coolant levels. I found out the hard way that its very easy to get to much oil in the system and it won't hold enough coolant to run efficiently
. In my case, draining it and recharging with straight freon (w/o oil) helped considerably.
It's impossible to measure it by "seat of the pants" estimates. I had estimated my vent temps to be 20*-30* (or even higher) warmer than the
truck. After measuring them I realized that there was only about a 10* difference, but what a difference that 10* makes. 
Just buy a digital meat thermometer (or steal your
, like I did 
). They're cheap, and will tell you what's going on.
Pskhaat
Tourer
- Thread starter
- #27
Thank everyone for everything so far.
I was really excited when kennyfj40 talked about hot vent temps without AC as even in cold weather I also believe I have abnormally warm air out of the vents almost like the heater is on. I
I just removed the radio and took a small video of the heater/evaporator actuation. I switched the heat slider twice half-way between hot cold, and then fully between hot and cold.
http://xepoch.com/mud/HeaterActuation.wmv
Sorry it's a Windows only movie.
You can see the valves and slides working from one end to the other, nothing looked disconnected. I'll go get a cheap thermometer and post back up too.
I was really excited when kennyfj40 talked about hot vent temps without AC as even in cold weather I also believe I have abnormally warm air out of the vents almost like the heater is on. I
I just removed the radio and took a small video of the heater/evaporator actuation. I switched the heat slider twice half-way between hot cold, and then fully between hot and cold.
http://xepoch.com/mud/HeaterActuation.wmv
Sorry it's a Windows only movie.
You can see the valves and slides working from one end to the other, nothing looked disconnected. I'll go get a cheap thermometer and post back up too.
alia176
SILVER Star
Scott,
sorry to hear about your A/C issues. Please check my thread "A/C system recharge questions" and see if it can shed any light on your troubles. I'm currently going through the A/C system on a '97 80.
The system is very simple and the parts are easily accessible. Tools R Us provided a link to purchase the A/C parts for a decent price should you want to replace any of the items.
You should be seeing a vent temp of 40 degrees F. The Aux fan should make this temp a reality in stop/go traffic.
Let me know if I can be of any help.
sorry to hear about your A/C issues. Please check my thread "A/C system recharge questions" and see if it can shed any light on your troubles. I'm currently going through the A/C system on a '97 80.
The system is very simple and the parts are easily accessible. Tools R Us provided a link to purchase the A/C parts for a decent price should you want to replace any of the items.
You should be seeing a vent temp of 40 degrees F. The Aux fan should make this temp a reality in stop/go traffic.
Let me know if I can be of any help.
Pskhaat
Tourer
- Thread starter
- #29
Today it is 111ºF outside. Drove to the local Ace to get a thermometer. AC worked moderately well on that leg of the drive. No data as no thermmeter yet. Hooked up OBDII feed into my laptop. Coolant temp fluctuated between 90ºC (194ºF) and 94ºC (201ºF).
Bought thermometer and back at truck measured 101ºF. Closed doors and waited until interior was 110ºF inside. Inside temps get much hotter if it was left for longer period of time.
Turned on truck, coolant read 97ºC and within a few seconds read back down at 91ºF.
Center vent temps (switched between both of them) were 88ºF. While driving home, vent temps never dropped below 79ºF going downhill several miles at 50mph and engine coolant read via OBDII at 91ºC. Crept back into the 80s as I entered my neighborhood.
Bought thermometer and back at truck measured 101ºF. Closed doors and waited until interior was 110ºF inside. Inside temps get much hotter if it was left for longer period of time.
Turned on truck, coolant read 97ºC and within a few seconds read back down at 91ºF.
Center vent temps (switched between both of them) were 88ºF. While driving home, vent temps never dropped below 79ºF going downhill several miles at 50mph and engine coolant read via OBDII at 91ºC. Crept back into the 80s as I entered my neighborhood.
Man... that doesn't sound good at all! I feel ya cause I'm here in Phx as well, and my A/C loves to kick off while I'm driving. I have yet to do the fan clutch fluid mod and the pusher fan mod, but those are coming. Yesterday I sprayed some A/C coil cleaner on my coils, let it sit and then rinse and knocked off all the bugs. Today while I was driving back to work, my A/C worked a tons better without warming up. Seems like you've done this already though. It's almost like your compressor isn't compressing the coolant enough. Maybe the compressor clutch is slipping or something. I don't know much, but if all else is fine, that's where I would look next. Good luck!
Grench
SILVER Star
So... did you or did you not check the cable that goes to the heater valve in the engine compartment on the firewall just to the PS of the EGR?
It is cable operated and prone to disconnect or getting blocked by a hose clamp sitting at the wrong angle. Don't ask me how I know.
The heater is perfectly able to overcome the AC if both are running full bore. Its like running the heat and AC at the same time. If that valve is stuck open... well, you get the idea. Makes the air real hot and dry.
I think others above have the right idea but may be pointing you to the wrong valve.
It is cable operated and prone to disconnect or getting blocked by a hose clamp sitting at the wrong angle. Don't ask me how I know.
The heater is perfectly able to overcome the AC if both are running full bore. Its like running the heat and AC at the same time. If that valve is stuck open... well, you get the idea. Makes the air real hot and dry.
I think others above have the right idea but may be pointing you to the wrong valve.
Pskhaat
Tourer
- Thread starter
- #32
Grench, you bet I did multiple times and replaced it too, that's why I'm curious if I should attempt blocking off the heater core altogether. The engine-side heater/coolant valve response ~linearly with the heat control slide as does the inside air valves behind the stereo (...or I believe it does)...I posted a video of that.
Uncle Grumpy
SILVER Star
Have you tried moving, who wants to live where it's 115? I forgot, it's a "dry" heat.
I don't have any expertise to add but I hope you get that fixed soon. What a pain in the arse.
I don't have any expertise to add but I hope you get that fixed soon. What a pain in the arse.
Grench
SILVER Star
IMHO your truck is probably overheating. The AC has a cutoff when engine temps climb. It seems to be pretty common on trucks with dubious coolant histories. Did you do a coolant flush & fill in recent memory? Change the thermostat? Condition of radiator?
My AC was cutting the AC on long uphills when it was 100* outside, etc... When I got the truck the coolant looked brown. Even though I did a serious 11 pass flush to clear on it, I still had the annoying overheat when the truck was under stress.
I went crazy with this when I put on the SC last year. We replaced the fan (special V6 instead of the SC kit one), fan clutch, '94 radiator, aux OEM pusher fan, water pump, eliminated the pipes for the rear heater, flushed with tap, flushed with distilled, filled 50/50 red & distilled.
Now its happy and Dan's dogs should be too. I didn't even have a problem a week ago when I was pulling a 26' motor home behind me on a strap 20 miles through the Sandhills.
Pskhaat
Tourer
- Thread starter
- #35
I've had this happen in the past and it is very noticeable temperature and RPM difference, not the case now. I believe the AC cut is like 99-100ºC? Trying to find that now, and if OBDII is correct I'm not there yet.
I had the HG PM'd 4-5 years ago at Slee's which at that time was a full radiator swap to the early-model style (can't remember the difference now), new water pump and fan clutch, complete flush &c &c.
I have flushed and filled with Toyota Red and distilled 2 summers ago, no noticeable junk in the overflow or effluent at that time.
Grench
SILVER Star
That would be the next step - eliminate the possibility that it is the hot coolant overpowering your AC. Its pretty easy to do too.
I'm curious... The AC has two lines connecting through the firewall. The high pressure side should be hot - careful. The low pressure side should be coming back cold. Is this the case on yours? Are there any bubbles in the sight glass? Bubbles can indicate a low charge.
What year is the truck? If it is '93 or '94 it would require the 'old' refrigerant (R12?). 1996 is R134a. If its an old truck and someone put new refrigerant in it, that could cause it to have issues too.
IMHO YMMV I'm not a mechanic etc...
alia176
SILVER Star
I think the A/C compressor cuts out when the coolant temp hits 226 deg F.
I'd be curious to see what your Low and High pressures are using a manifold gauge.
I'd be curious to see what your Low and High pressures are using a manifold gauge.
Were the expansion valve and filter/dryer replaced when the dealer or AC specialty shop evacuated and recharged the system? If the dryer is saturated with moisture and is polluting the freon each time the system is refilled, the expansion valve may be icing up and impeding the state change from liquid to gaseous in the evaporator.
On a less likely note, is the blue hub timing adjusted to a known opening point in accordance with LandTank's method?
On a less likely note, is the blue hub timing adjusted to a known opening point in accordance with LandTank's method?
Pskhaat
Tourer
- Thread starter
- #40
I forgot to mention the dryer being replaced, yes. No on the expansion valve, however I really can't imagine it icing up at all, but I would assume someone would have noticed the huge pressure change at some point when it was last serviced and it was 20ºF cooler than it is lately.
As per the repeated success of ToolsRUs, I did not adjust the clutch valve, only the 10kcst fill.
One other data point. I just sat there and watched the sight glass. It appears about every 20 seconds or so I get a distinct clouding and then it goes away, with a small amount of clouding 10 seconds thereafter. I recorded 2 iterations of this cycle in link below. Fast forward to 18 seconds or so to see cloudy. Any thoughts?
MPEG http://xepoch.com/mud/MOV01087.MPG , or
WMV http://xepoch.com/mud/PeriodicCloudy.wmv (smaller)
What would cause this, is this expected? I need to go buy a manifold gauge set.
As per the repeated success of ToolsRUs, I did not adjust the clutch valve, only the 10kcst fill.
One other data point. I just sat there and watched the sight glass. It appears about every 20 seconds or so I get a distinct clouding and then it goes away, with a small amount of clouding 10 seconds thereafter. I recorded 2 iterations of this cycle in link below. Fast forward to 18 seconds or so to see cloudy. Any thoughts?
MPEG http://xepoch.com/mud/MOV01087.MPG , or
WMV http://xepoch.com/mud/PeriodicCloudy.wmv (smaller)
What would cause this, is this expected? I need to go buy a manifold gauge set.
