AC Issue
03-14-2009, 06:28 PM
#21
Unless someone installed a chiller in this car, unloading is not a common cycling routine.
What do I need to make a ******* video showing you how BOTH of my LS1 camaros cycle with the clutch?
The compressor might unload as a last ditch effort to keep from blowing itself off the engine.
03-14-2009, 09:49 PM
#22
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From reading your post the only thing I see that you are worried about is that there is no air flow. can you hear the blower motor speed up and down with the different speeds?
Also since out compressors are fixed displacement compressors with orifice tubes they will cycle off. They cycle off from the pressure on the low side. Once it the low side or inlet of the evap gets low/cool enough the switch will cycle it off. Thus commanding the fans to go off with it.
Yes. your fans do come on when you turn the AC on. They come on because the compressor pumps out a hot refrigerant and it goes through the condenser to cool off. The fans are there to pull air through so that the refrigerant can cool off.
Any other questions?
Also since out compressors are fixed displacement compressors with orifice tubes they will cycle off. They cycle off from the pressure on the low side. Once it the low side or inlet of the evap gets low/cool enough the switch will cycle it off. Thus commanding the fans to go off with it.
Yes. your fans do come on when you turn the AC on. They come on because the compressor pumps out a hot refrigerant and it goes through the condenser to cool off. The fans are there to pull air through so that the refrigerant can cool off.
Any other questions?
03-15-2009, 09:59 AM
#23
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WRONG, it cycles on and off by engaging and disengaging the clutch.
Unless someone installed a chiller in this car, unloading is not a common cycling routine.
What do I need to make a ******* video showing you how BOTH of my LS1 camaros cycle with the clutch?
The compressor might unload as a last ditch effort to keep from blowing itself off the engine.
Unless someone installed a chiller in this car, unloading is not a common cycling routine.
What do I need to make a ******* video showing you how BOTH of my LS1 camaros cycle with the clutch?
The compressor might unload as a last ditch effort to keep from blowing itself off the engine.
03-15-2009, 10:35 AM
#24
Hey, does it matter? people ask if they should add freon because the belt snapped and it's not blowing cold air.
Do you think they give a damn if it unloads?
no cold=add refrigerant, we all know it's that, easy right
Do you think they give a damn if it unloads?
no cold=add refrigerant, we all know it's that, easy right
03-15-2009, 11:41 AM
#25
Staring to get confusing 1. Customer(me) complaint. A/C after its been on for about a 1/2 hour the car starts getting warm. I turn the blower fan up and no appreciable gain in air flow. The blower motor audible runs faster with a slight distressed sound. Switch to MAX (recirculate) HI/LO, floor no difference in cooling or air flow. A/C runs fine for the first 1/2 hour the blower works great on all speeds.
2. I'm pretty sure the evaporator is freezing up. So what’s causing it? Took it to Ice Cold Air in Orlando. The manager there told me the compressor had good specs and the charge was fine but the A/C wasn't cycling! That’s why it was freezing up. He said," Someone probably twisted the wires together from the pressure switch somewhere. He offered to have his tech start tracing the wires from the switch heading into the car. He also said,” the procedure when this happens is to reset/reflash the PCM as the ground signal comes from there". I wasn't interested in paying for a fishing expedition. It sounded possible to me as the car has sticker saying it has a remote starting system. It doesn’t but it probably did at one time as the wires under the dash near the steering wheel are all butchered some twisted are together others taped up for example my engine will turn over with the clutch not depressed. I’m slowly fixing that mess. I headed home for a 45 min ride. I cycled the A/C every 5 or so minutes on the way home manually and it stayed as cold as a preverbal witch’s Tit.
3. I got home and broke out my Helms and EFI Live. I figured wrong that Body Control Module would work the A/C. I discovered on the wiring schematic that it doesn't use the Body Control Module. See Schematic attached.
What I've concluded so far:
a) The PCM monitors the Pressure switch located in the line. When the High side get high enough the PCM will turn on the Engine coolant fan. (the condenser for the A/C is located in front of the radiator.) It figures (I assume) that the High Pressure High Temp Gas Refrigerant isn't cooling and turn into a High pressure Lower Temp Liquid efficiently and that’s what is causing the Pressure build up? If pressure gets too high(410psi) or too low (30psi)then the PCM will shut the compressor down via the clutch. It will reactivate when pressure returns to 250 to 150 psi. on the high side.
b) The engine coolant fans can be ordered on from the PCM when certain parameters are met for support of the A/C system. See image of PIDs from efi live.
What I don't know, can't find. What is the role of the Compressor Control Valves on the back of the compressor? could these elusive little buggers that are causing all the conflicting comments???? They obviously operate automously (cool word) from the PCM.
I have the V7 compressor.
thanks Ed
2. I'm pretty sure the evaporator is freezing up. So what’s causing it? Took it to Ice Cold Air in Orlando. The manager there told me the compressor had good specs and the charge was fine but the A/C wasn't cycling! That’s why it was freezing up. He said," Someone probably twisted the wires together from the pressure switch somewhere. He offered to have his tech start tracing the wires from the switch heading into the car. He also said,” the procedure when this happens is to reset/reflash the PCM as the ground signal comes from there". I wasn't interested in paying for a fishing expedition. It sounded possible to me as the car has sticker saying it has a remote starting system. It doesn’t but it probably did at one time as the wires under the dash near the steering wheel are all butchered some twisted are together others taped up for example my engine will turn over with the clutch not depressed. I’m slowly fixing that mess. I headed home for a 45 min ride. I cycled the A/C every 5 or so minutes on the way home manually and it stayed as cold as a preverbal witch’s Tit.
3. I got home and broke out my Helms and EFI Live. I figured wrong that Body Control Module would work the A/C. I discovered on the wiring schematic that it doesn't use the Body Control Module. See Schematic attached.
What I've concluded so far:
a) The PCM monitors the Pressure switch located in the line. When the High side get high enough the PCM will turn on the Engine coolant fan. (the condenser for the A/C is located in front of the radiator.) It figures (I assume) that the High Pressure High Temp Gas Refrigerant isn't cooling and turn into a High pressure Lower Temp Liquid efficiently and that’s what is causing the Pressure build up? If pressure gets too high(410psi) or too low (30psi)then the PCM will shut the compressor down via the clutch. It will reactivate when pressure returns to 250 to 150 psi. on the high side.
b) The engine coolant fans can be ordered on from the PCM when certain parameters are met for support of the A/C system. See image of PIDs from efi live.
What I don't know, can't find. What is the role of the Compressor Control Valves on the back of the compressor? could these elusive little buggers that are causing all the conflicting comments???? They obviously operate automously (cool word) from the PCM.
I have the V7 compressor.
thanks Ed
Last edited by BRD-PREY; 03-15-2009 at 11:42 AM. Reason: missing attachments
03-15-2009, 12:02 PM
#27
Can you manually control the compressor clutch with EFI Live? I can with HPTuners.
1st I'd try to shut it off like that.
2nd I'd try to shut it off by pulling the plug off the pressure switch.
If either of these shut it off, then the pressure switch is bad.
The compressor control valves bleed pressure off internally when it gets too high. It's not your problem.
Assuming the shop diagnosed it properly.
1st I'd try to shut it off like that.
2nd I'd try to shut it off by pulling the plug off the pressure switch.
If either of these shut it off, then the pressure switch is bad.
The compressor control valves bleed pressure off internally when it gets too high. It's not your problem.
Assuming the shop diagnosed it properly.
03-15-2009, 12:06 PM
#28
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Unplug the connector to the pressure shutoff switch next to the evap. With it unplugged turn the ac on. If the compressor clutch engages the wiring for the cutoff switch is shorted. if It does not come on the switch is your problem.
03-15-2009, 12:13 PM
#29
When the High side get high enough the PCM will turn on the Engine coolant fan. (the condenser for the A/C is located in front of the radiator.) It figures (I assume) that the High Pressure High Temp Gas Refrigerant isn't cooling and turn into a High pressure Lower Temp Liquid efficiently and that’s what is causing the Pressure build up?
High efficiency house units cycle the condenser fan to save electricity.
Automotive condenser fans cycle to save draw on the electrical system, avoid from over cooling the engine and the refrigerant, etc.
03-15-2009, 12:18 PM
#30
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Thats normal operation. Look at the outdoor unit on your house, the condenser fan runs with the compressor. (just like your engine fan runs with your engine)
High efficiency house units cycle the condenser fan to save electricity.
Automotive condenser fans cycle to save draw on the electrical system, avoid from over cooling the engine and the refrigerant, etc.
High efficiency house units cycle the condenser fan to save electricity.
Automotive condenser fans cycle to save draw on the electrical system, avoid from over cooling the engine and the refrigerant, etc.
03-15-2009, 01:07 PM
#31
When I have HP Tuners logging my high fan kicks on and off way lower than the set point only when the AC is on.
See what I mean, this thread is a big mess of ******* bullshit.
If someone doesn't have the tools to fix AC, TAKE IT TO A SHOP.
03-15-2009, 03:13 PM
#32
9000th01ss I'm just trying to make sure the A/C that fixes it knows what they are doing and doesn't just part chase. I don't have much confidents in shops these days.
Still not sure where the confusing coming from, NBM-LS1, I including my tune data from EFI Live. It shows my Fan#2 is set to go on a/c pressure 1710psi and disable 1434psi.
Not sure about what the auto recirculation setting is. Doesn't this means that A/C controls the cooling fans?
The A/C control goes to the PCM, doesn't that mean the Pcm can command the A/C on and off. EFI Live shutting the compressor on and off would be the same right.
Its the getting too cold freezing the evap sensing system (circuit
0 (how ever that happens) that appears to be the problem. I'm in the middle of working on something, when I get done I will try your suggestions.
Thanks for everyone input.
Ed
Still not sure where the confusing coming from, NBM-LS1, I including my tune data from EFI Live. It shows my Fan#2 is set to go on a/c pressure 1710psi and disable 1434psi.
Not sure about what the auto recirculation setting is. Doesn't this means that A/C controls the cooling fans?
The A/C control goes to the PCM, doesn't that mean the Pcm can command the A/C on and off. EFI Live shutting the compressor on and off would be the same right.
Its the getting too cold freezing the evap sensing system (circuit
0 (how ever that happens) that appears to be the problem. I'm in the middle of working on something, when I get done I will try your suggestions.
Thanks for everyone input.
Ed
