Air conditioning seems weak

[Computron]

Hi all,

I have a 2004 that I've been driving around in 80 degree heat, which if you ask me is a pretty mild heat considering many parts of the country. Anyways, it seems like the AC is not very cool. I often have to set it to 61 and then turn the blower to between middle and max speed just to keep comfortable. Leaving it on auto doesn't result in fast enough fan speed to keep cool.

My question for you other nsx owners out there is... Is this normal? Is the nsx AC just underpowered or do I need to get the freon level checked or something? It seems like for such a small cabin area, it should really get the interior cool. Maybe I'm too used to my Acura RL or Honda Pilot but those vehicles can get their much larger interiors cold to the point that I have to turn the set temp up to 70 to not freeze.

I welcome any thoughts on this...

 

[clean_green]

This is not normal behavior. I live in Texas where 100 degree F is common in the summer and the A/C in my '02 cools very well. I have the climate control set on full auto and 68 degrees and it always cools down quickly and feels great! Get your refrigerant checked/topped.

 

[Larry Bastanza]

You should run the climate control diagnostics to see if it is fully functional. This could be a few things, like low freon, but for sure test the CC first.

 

[Computron]

You should run the climate control diagnostics to see if it is fully functional. This could be a few things, like low freon, but for sure test the CC first.

Will the CC tests tell me anything if all the functions work currently? I mean all the button and knob functions work as they should. I get different fan speeds, the recirc vs fresh air works, the temp dial works, the air flow positions work... it's just it doesn't seem to get too cold.

I'm thinking I should have a look at my site glass for bubbles first. What do you think?

 

[JD Cross]

I have a black/black NSX and with the large windshield it gets a lot of solar gain.
First why not buy an A/C thermometer at one of the auto parts stores and check the air temp with A/C on full.
Then you'll know what air temp your system is putting out.

If the air temp is high, possibly you've developed a leak and your 134a is low.
You could top the refrigerant up but ask the shop to put in some dye so if you have a leak you can find out where.

And by all means read your shop manual and check the sight glass

 

[Old Guy]

As JD notes, the NSX has a great big green house and with a black interior, gets really toasty when sitting in the sun. If mine has been sitting in the sun for 15 minutes or more, it will be blowing cold air within 30 seconds; but, take 5 - 7 minutes to bring the cabin temperature down because of the heat energy stored in the body structure.

I have also concluded that the temperature displayed on the CCU refers to something other than cabin temperature, or its just a placebo. I pretty much end up running the CCU in manual mode. If you turn the temperature setting to the lowest on manual and it is not blowing frigid air within 30 seconds or so (use a thermometer as JD suggests) then do as others suggest and get your system checked.

 

[Computron]

Thanks for all your comments. I took my NSX for a thorough drive today and found that the vent temps ranged from 38-44 degrees on an 80 degree day which seems to be very good. What the problem seems to be is that if I leave it in Full Auto, the fan speed never automatically goes up very high. If I do as Old Guy says and just run it manually, the perfect setting seems to be the fan speed on just above half way. Then it cools extremely well. If I leave it on Full auto, even set at 61 degrees (which is 1 degree up from max cool at 60), the fan speed is very low. The car seems to not want to turn up the fan speed very much on its own. Of course at 60, it maxes everything out.

Does anyone else experience this?

 

[JD Cross]

Thanks for all your comments. I took my NSX for a thorough drive today and found that the vent temps ranged from 38-44 degrees on an 80 degree day which seems to be very good. What the problem seems to be is that if I leave it in Full Auto, the fan speed never automatically goes up very high. If I do as Old Guy says and just run it manually, the perfect setting seems to be the fan speed on just above half way. Then it cools extremely well. If I leave it on Full auto, even set at 61 degrees (which is 1 degree up from max cool at 60), the fan speed is very low. The car seems to not want to turn up the fan speed very much on its own. Of course at 60, it maxes everything out.
Does anyone else experience this?

Could be your CCU circuit board is starting to fail.
It's a common failure after 22 years.
Mine did.
Briank fixes them

 

[Larry Bastanza]

Also could be the aspirator fan in the console (behind the little slots near your ebrake handle in the dash)

 

[Computron]

Wow... I didn't realize there was an aspirator fan involved. What exactly does it do? Does it deal with the interior temperature sensor?

 

[JD Cross]

Wow... I didn't realize there was an aspirator fan involved. What exactly does it do? Does it deal with the interior temperature sensor?

It blows air over a temp sensor which ties into the CCU.
Would be best if you download the free shop manual from the Wiki and read up on your A/C system.
You can learn about your system and answer all of your questions.
Too many questions to go item by item on the forums.

 

[Old Guy]

Or you could just leave it on manual! If the fan speed control works and the temperature goes up and down and all the vent doors open and close like they are supposed to, my inclination would be to leave it alone. Send it to Brian when the important stuff stops working.

Its just like the NSX transmission. Everybody seems to think the manual is better than the Auto. Same thing with the climate control:smile:.

As an aside, if your aspirator fan is getting plugged up it will usually get noisy. A very annoying click click all the time. The fan is located behind that little grill in front of the shifter.