AC issues (1 Viewer)

[Tstx92]

I’m sorry to revive a topic that has already been discussed at length. I’ve read as many of the other threads on this issue but I’m still at a dead end, as is my mechanic.

so, my ac compressor was leaking so I had it replaced, along with the evaporator. The parts wfrom Performance Radiator, here in Houston.

After it having been replaced, I noticed that, only in drive and at a complete stop, the ac light starts flashing and the air ceases to be cold.

after doing some research, I started with changing the relay, and then checked/secured the wiring.
As the problem persisted, I returned to my mechanic who had been unable to fix the problem.

Today I decided to take it up to the dealership. They are telling me that it’s the compressor, specifically the clutch, and that and OEM compressor is necessary. I generally use OEM parts when working on my land cruiser, I just don’t know much about AC systems and don’t have the equipment so I had to have my tech do the job.
Is this true that only an OEM compressor is necessary? And other insights?

 

[flintknapper]

I’m sorry to revive a topic that has already been discussed at length. I’ve read as many of the other threads on this issue but I’m still at a dead end, as is my mechanic.

so, my ac compressor was leaking so I had it replaced, along with the evaporator. The parts wfrom Performance Radiator, here in Houston.

After it having been replaced, I noticed that, only in drive and at a complete stop, the ac light starts flashing and the air ceases to be cold.

after doing some research, I started with changing the relay, and then checked/secured the wiring.
As the problem persisted, I returned to my mechanic who had been unable to fix the problem.

Today I decided to take it up to the dealership. They are telling me that it’s the compressor, specifically the clutch, and that and OEM compressor is necessary. I generally use OEM parts when working on my land cruiser, I just don’t know much about AC systems and don’t have the equipment so I had to have my tech do the job.
Is this true that only an OEM compressor is necessary? And other insights?

NO....NOT true that ONLY an OEM will work. But....it is TRUE that your compressor and clutch (regardless the manufacturer) needs to be in proper working order. And I can tell you that dealerships don't 'fix' things any longer they are pretty much nothing more than parts re-placers (if you are lucky enough to get the right diagnosis).

IF you are telling us that the system works (cools) other than being in drive and stopped (or at low speed) I wouldn't be looking to the compressor at all.

 

[Tstx92]

NO....NOT true that ONLY an OEM will work. But....it is TRUE that your compressor and clutch (regardless the manufacturer) needs to be in proper working order. And I can tell you that dealerships don't 'fix' things any longer they are pretty much nothing more than parts re-placers (if you are lucky enough to get the right diagnosis).

IF you are telling us that the system works (cools) other than being in drive and stopped (or at low speed) I wouldn't be looking to the compressor at all.

Okay good. In that case, where would you be looking?

 

[flintknapper]

Okay good. In that case, where would you be looking?

First look at your fan clutch and see that it is working properly, there should be a good amount of air being pulled through your condenser, radiator and across your engine. Do you have a condenser (Aux fan) on your vehicle? Most early 100 series 98-2000 had them? IF so...is it working.

When your compressor was replaced did it come with a new clutch or was the old one installed on it?

 

[Tstx92]

First look at your fan clutch and see that it is working properly, there should be a good amount of air being pulled through your condenser, radiator and across your engine. Do you have a condenser (Aux fan) on your vehicle? Most early 100 series 98-2000 had them? IF so...is it working.

When your compressor was replaced did it come with a new clutch or was the old one installed on it?

Fan clutch appears to be in good shape, judging off of its tension when motor is cold. Also, the truck never gets hot.

I do have a condenser and I'm almost certain that it was also replaced when the compressor was. I'll have to double check on the clutch, I think that it came with a brand new one but not 100% sure.

 

[flintknapper]

Fan clutch appears to be in good shape, judging off of its tension when motor is cold. Also, the truck never gets hot.

I do have a condenser and I'm almost certain that it was also replaced when the compressor was. I'll have to double check on the clutch, I think that it came with a brand new one but not 100% sure.

Most compressors do come with a new clutch but you can buy them bare and swap a clutch onto it. In which case you'd want to be sure the air gap is correct and that it engages properly (not slipping). It's normal for an A/C to be less efficient at low speed (engine speed and vehicle speed) for the obvious reasons, but you should have relatively cool air at the vents even at idle (at least 55 degrees) on Hot Houston Days. Then better at highway speeds.

If you have vent temps 30°F below the ambient (outside air temp) then your system is working pretty well. Any more than that...all the better.

I'm about 3 hrs North of you and we share the same weather....so I know how critical it is to have the A/C working properly.

It would be worthwhile to have the refrigerant charge (pressures) checked.

I would also be interested to hear a more detailed explanation from the dealer as to why they think the clutch is at fault.

 

[highkick05]

What kind of AC mechanic replaces parts and gives you back a system that does not work? Baffling.

 

[beachedwhale]

tstx92 i am going through this exact same problem. i too live in houston and today hit 101 on my thermometer. on the move 30mph and over i can freeze myself out in nothing flat. below that speed it gets really hot like dont go through a drive thru and eat in the parking lot kind of hot.

i am trying to work through these issues too and will post here if i figure it out.

 

[flintknapper]

tstx92 i am going through this exact same problem. i too live in houston and today hit 101 on my thermometer. on the move 30mph and over i can freeze myself out in nothing flat. below that speed it gets really hot like dont go through a drive thru and eat in the parking lot kind of hot.

i am trying to work through these issues too and will post here if i figure it out.

Same advice as given to the OP, low speed performance of your A/C system will always be less than at higher engine/vehicle speed. Simply because the compressor is not turning as fast and less air is going across the condenser.

So....in Texas and other hot climates I highly recommend doing a Fan Clutch 'mod' (drain and refill with a higher CST fluid, I use 20K) AND if your vehicle has a condenser/Aux fan be sure it is working. If your vehicle doesn't have one....add one.

Adding A/c Condenser Fan to 03+ LX470

@LandCruiserPhil offers a great kit for this, which is hands down much more painless than what I'm about to explain below, however, you could do the wiring like I did and still use his kit. Here is the original thread: How to get peak AC performance from your 2003+ 100 series I needed a...

forum.ih8mud.com

It should go without saying...that your system needs to be fully charged with refrigerant as well.

IF you have rear air and don't have passengers in the back...don't run it except to cool the vehicle initially. I've found that running the rear A/C is parasitic to front A/C vent temps by about 8 degrees.

Get a pocket/vent thermometer.....place it in your center vent and see what the actual temps are at various speeds and conditions. If its 100°F outside (like it was here yesterday) then a 60°F vent temp is pretty darn good.

 

[beachedwhale]

Same advice as given to the OP, low speed performance of your A/C system will always be less than at higher engine/vehicle speed. Simply because the compressor is not turning as fast and less air is going across the condenser.

So....in Texas and other hot climates I highly recommend doing a Fan Clutch 'mod' (drain and refill with a higher CST fluid, I use 20K) AND if your vehicle has a condenser/Aux fan be sure it is working. If your vehicle doesn't have one....add one.

Adding A/c Condenser Fan to 03+ LX470

@LandCruiserPhil offers a great kit for this, which is hands down much more painless than what I'm about to explain below, however, you could do the wiring like I did and still use his kit. Here is the original thread: How to get peak AC performance from your 2003+ 100 series I needed a...

forum.ih8mud.com

It should go without saying...that your system needs to be fully charged with refrigerant as well.

IF you have rear air and don't have passengers in the back...don't run it except to cool the vehicle initially. I've found that running the rear A/C is parasitic to front A/C vent temps by about 8 degrees.

Get a pocket/vent thermometer.....place it in your center vent and see what the actual temps are at various speeds and conditions. If its 100°F outside (like it was here yesterday) then a 60°F vent temp is pretty darn good.

I have a ac gauge set and she is full of refrigerant. fan clutch works and it has an electronic fan on the condenser that runs strong. i know for a fact po had put stop leak in the system and it had drained completely of r134a. i used a leak detector and found the schrader valve to be the culprit. i am wondering if the oxegen getting in the lines made the stop leak gum up in the condenser so when at lower speeds it doesnt flow as well. could be in the expansion valve as well as it kind of makes a whine/whistle (hard to describe) the gets more pronounced when the rpm's increase pushing more refrigerant through

 

[flintknapper]

I have a ac gauge set and she is full of refrigerant. fan clutch works and it has an electronic fan on the condenser that runs strong. i know for a fact po had put stop leak in the system and it had drained completely of r134a. i used a leak detector and found the schrader valve to be the culprit. i am wondering if the oxegen getting in the lines made the stop leak gum up in the condenser so when at lower speeds it doesnt flow as well. could be in the expansion valve as well as it kind of makes a whine/whistle (hard to describe) the gets more pronounced when the rpm's increase pushing more refrigerant through

TXV making a whining or hissing sound (from behind the glove box area) is generally an indicator it has a problem or the refrigerant charge is incorrect.

 

[ibrahim83]

I’m sorry to revive a topic that has already been discussed at length. I’ve read as many of the other threads on this issue but I’m still at a dead end, as is my mechanic.

so, my ac compressor was leaking so I had it replaced, along with the evaporator. The parts wfrom Performance Radiator, here in Houston.

After it having been replaced, I noticed that, only in drive and at a complete stop, the ac light starts flashing and the air ceases to be cold.

after doing some research, I started with changing the relay, and then checked/secured the wiring.
As the problem persisted, I returned to my mechanic who had been unable to fix the problem.

Today I decided to take it up to the dealership. They are telling me that it’s the compressor, specifically the clutch, and that and OEM compressor is necessary. I generally use OEM parts when working on my land cruiser, I just don’t know much about AC systems and don’t have the equipment so I had to have my tech do the job.
Is this true that only an OEM compressor is necessary? And other insights?

Whats up man,

I have a 2001 GS300 sitting at my shop right now along with two "new" compressors. Same thing. Ice cold, even at idle, Until you put the car in gear and the rpm drops. According to all my systems, the rpm sensor in the compressor is giving a signal of too low rpm causing the system to turn off. something about cheap aftermarket sensors cause this issue.

Toyota does that for protection because it's a one belt system. when it senses a difference, it thinks the compressor is seizing, and to save the belt, it decouples the compressor via it's clutch.

Customer was warned not to buy anything but denso, but they didn't listen. So now i'm collecting labor for two compressor jobs and we're finally using a Denso unit.

 

[Tstx92]

Whats up man,

I have a 2001 GS300 sitting at my shop right now along with two "new" compressors. Same thing. Ice cold, even at idle, Until you put the car in gear and the rpm drops. According to all my systems, the rpm sensor in the compressor is giving a signal of too low rpm causing the system to turn off. something about cheap aftermarket sensors cause this issue.

Toyota does that for protection because it's a one belt system. when it senses a difference, it thinks the compressor is seizing, and to save the belt, it decouples the compressor via it's clutch.

Customer was warned not to buy anything but denso, but they didn't listen. So now i'm collecting labor for two compressor jobs and we're finally using a Denso unit.

Good to hear. This is pretty much the same conclusion that my shop reached and they're putting in a Denso unit as we speak. Fingers crossed!

 

[ibrahim83]

Good to hear. This is pretty much the same conclusion that my shop reached and they're putting in a Denso unit as we speak. Fingers crossed!

Just finished installing the denso. Everything works as it should now.

 

[beachedwhale]

Just finished installing the denso. Everything works as it should now.

Adding the denso unit to my to do list. thank you!

 

[Tstx92]

Denso unit seemed to have fixed it!

 

[sonk76]

Could someone provide clarity on exactly which sensor was replace and with which Denso part (part number / source would be awesome!)?

 

[ibrahim83]

Could someone provide clarity on exactly which sensor was replace and with which Denso part (part number / source would be awesome!)?

I got a Japanese made denso direct fit from AutoZone. But then again it was a gs.

 

[Tstx92]

Could someone provide clarity on exactly which sensor was replace and with which Denso part (part number / source would be awesome!)?

In my case, the entire compressor was replaced. I'm honestly not sure if the issue was the compressor or the sensor withing the compressor, nor am I sure if the sensor can be replaced separate from the compressor. All that being said, I, obviously, don't have a part number for the sensor.

 

[sonk76]

In my case, the entire compressor was replaced. I'm honestly not sure if the issue was the compressor or the sensor withing the compressor, nor am I sure if the sensor can be replaced separate from the compressor. All that being said, I, obviously, don't have a part number for the sensor.

Got it, thanks.