A/C Sometimes Blows Cold, Sometimes Not
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A/C Sometimes Blows Cold, Sometimes Not
05 AP2 with about 45k miles. Don't use the A/C too much due to driving around with the top down most of the time, however, the last time I used the A/C at it's coldest setting with recirculation on, the air would sometimes be somewhat cold and other times warmer. Even at its coldest setting, the air is not as cold as in other cars I've been in such as a Honda Civic and Toyota Solara.
Anybody have an idea of the issue here?
Anybody have an idea of the issue here?
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A few things to consider.
The A/C unit on this car will cool the air by about 20-30f from outside.
WOT/High Revs may and/or will have the compressor turn off.
Since the unit isn't consistently warm, you likely don't have a leak in the system. My 04 last summer was off 1psi on the high and low side. I doubt yours is more than that.
The A/C unit on this car will cool the air by about 20-30f from outside.
WOT/High Revs may and/or will have the compressor turn off.
Since the unit isn't consistently warm, you likely don't have a leak in the system. My 04 last summer was off 1psi on the high and low side. I doubt yours is more than that.
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on real hot days mine will blow cold air for few hours and out of nowhere i get some like room temp air for a few minutes,then it goes away, think happens when my spal fan kicks in full speed. its not low on ac gas, i put new lines in to tuck them away from header
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Miguel, your problem sounds similar to mine. I'll be driving around with the air coming out cold, then all of a sudden it goes to room temp air and then back to cold. My other issue is this A/C set on its coldest setting still isn't as cold as I believe it should be. I'll get a thermometer in the vent to see the air temp and report back.
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Do any of you have an actual coolant temp gauge to confirm what I'm about to say?
On a recent roadtrip through Zion Park, Bryce Canyon, Grand Canyon and Death Valley, a couple of S2000s noticed an interesting trait. Mine is an AP1 and the other was an AP2. Both of us remarked that there were times when the A/C would stop blowing cold air and just blew unconditioned air from the outside (which was quite hot ~104). When the engine was subjected to unusual load such as going up an incline and lower road speed, my engine coolant temp went up to about 237*F. This is also about when an AP1 hits "4 bars". I don't how many bars an AP2 would be at this temp. Compound this with lower road speeds that reduced the amount of air going through the rad and this aggravated the high coolant temps. Once we got back up to higher road speeds, this situation never occurred as the coolant temps came back down to a more reasonable level.
This is when the A/C stopped working. I believe it's a sort of built in failsafe where the ECU tells the A/C compressor to de-clutch so as to remove a bit of load from the engine at a time when it's laboring the most. During these hot conditions, the rad never blew and the engine never "over-heated" as such even though it was running extremely hot.
My car did it the most as I've got a FMIC sitting in front of the engine rad.
On a recent roadtrip through Zion Park, Bryce Canyon, Grand Canyon and Death Valley, a couple of S2000s noticed an interesting trait. Mine is an AP1 and the other was an AP2. Both of us remarked that there were times when the A/C would stop blowing cold air and just blew unconditioned air from the outside (which was quite hot ~104). When the engine was subjected to unusual load such as going up an incline and lower road speed, my engine coolant temp went up to about 237*F. This is also about when an AP1 hits "4 bars". I don't how many bars an AP2 would be at this temp. Compound this with lower road speeds that reduced the amount of air going through the rad and this aggravated the high coolant temps. Once we got back up to higher road speeds, this situation never occurred as the coolant temps came back down to a more reasonable level.
This is when the A/C stopped working. I believe it's a sort of built in failsafe where the ECU tells the A/C compressor to de-clutch so as to remove a bit of load from the engine at a time when it's laboring the most. During these hot conditions, the rad never blew and the engine never "over-heated" as such even though it was running extremely hot.
My car did it the most as I've got a FMIC sitting in front of the engine rad.
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Miguel, your problem sounds similar to mine. I'll be driving around with the air coming out cold, then all of a sudden it goes to room temp air and then back to cold. My other issue is this A/C set on its coldest setting still isn't as cold as I believe it should be. I'll get a thermometer in the vent to see the air temp and report back.
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Do any of you have an actual coolant temp gauge to confirm what I'm about to say?
On a recent roadtrip through Zion Park, Bryce Canyon, Grand Canyon and Death Valley, a couple of S2000s noticed an interesting trait. Mine is an AP1 and the other was an AP2. Both of us remarked that there were times when the A/C would stop blowing cold air and just blew unconditioned air from the outside (which was quite hot ~104). When the engine was subjected to unusual load such as going up an incline and lower road speed, my engine coolant temp went up to about 237*F. This is also about when an AP1 hits "4 bars". I don't how many bars an AP2 would be at this temp. Compound this with lower road speeds that reduced the amount of air going through the rad and this aggravated the high coolant temps. Once we got back up to higher road speeds, this situation never occurred as the coolant temps came back down to a more reasonable level.
This is when the A/C stopped working. I believe it's a sort of built in failsafe where the ECU tells the A/C compressor to de-clutch so as to remove a bit of load from the engine at a time when it's laboring the most. During these hot conditions, the rad never blew and the engine never "over-heated" as such even though it was running extremely hot.
My car did it the most as I've got a FMIC sitting in front of the engine rad.
On a recent roadtrip through Zion Park, Bryce Canyon, Grand Canyon and Death Valley, a couple of S2000s noticed an interesting trait. Mine is an AP1 and the other was an AP2. Both of us remarked that there were times when the A/C would stop blowing cold air and just blew unconditioned air from the outside (which was quite hot ~104). When the engine was subjected to unusual load such as going up an incline and lower road speed, my engine coolant temp went up to about 237*F. This is also about when an AP1 hits "4 bars". I don't how many bars an AP2 would be at this temp. Compound this with lower road speeds that reduced the amount of air going through the rad and this aggravated the high coolant temps. Once we got back up to higher road speeds, this situation never occurred as the coolant temps came back down to a more reasonable level.
This is when the A/C stopped working. I believe it's a sort of built in failsafe where the ECU tells the A/C compressor to de-clutch so as to remove a bit of load from the engine at a time when it's laboring the most. During these hot conditions, the rad never blew and the engine never "over-heated" as such even though it was running extremely hot.
My car did it the most as I've got a FMIC sitting in front of the engine rad.
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From: Queen City, NC
Some thoughts...
1. The AC plumbing in the S2000 is short, so it doesn't hold much refrigerant and is more quickly heat-saturated, resulting in warmer air. You notice this more on the really hot days when the system is taxed - if you don't regularly use the AC you won't notice that it always happens and has since new.
2. On hot days, the system will pull heat and have a "hot spot" in the line that cycles through, which you will feel as the air getting colder/warmer.
3. Because the plumbing is short, refrigerant cycles through the system quicker, so it may not be fully cold when the heat transfer from air occurs, thus warmer air at times as it takes several cycles for the system to completely cool and normalize after taking a large amount of heat initially.
4. If the system needs to be "topped off" (S2000s seem to come from the factory with a little less than full refrigerant)you will also get the warm/cool cycle.
5. The AC compressor has a clutch that kicks in at a certain throttle point for maximum engine power, so flooring the gas will turn the AC off temporarily (but not the blower fan)and you'll get warm air through the vents.
Does the AC work fine on mild days? Does the system eventually normalize and blow air at a constant cool temp after the refrigerant has had time to cycle through and dispel heat? Is the system topped off or full enough? Are you seeing a relationship between flooring the gas and getting warm air?
1. The AC plumbing in the S2000 is short, so it doesn't hold much refrigerant and is more quickly heat-saturated, resulting in warmer air. You notice this more on the really hot days when the system is taxed - if you don't regularly use the AC you won't notice that it always happens and has since new.
2. On hot days, the system will pull heat and have a "hot spot" in the line that cycles through, which you will feel as the air getting colder/warmer.
3. Because the plumbing is short, refrigerant cycles through the system quicker, so it may not be fully cold when the heat transfer from air occurs, thus warmer air at times as it takes several cycles for the system to completely cool and normalize after taking a large amount of heat initially.
4. If the system needs to be "topped off" (S2000s seem to come from the factory with a little less than full refrigerant)you will also get the warm/cool cycle.
5. The AC compressor has a clutch that kicks in at a certain throttle point for maximum engine power, so flooring the gas will turn the AC off temporarily (but not the blower fan)and you'll get warm air through the vents.
Does the AC work fine on mild days? Does the system eventually normalize and blow air at a constant cool temp after the refrigerant has had time to cycle through and dispel heat? Is the system topped off or full enough? Are you seeing a relationship between flooring the gas and getting warm air?