I picked up my 2008 Civic last October because I had a 90 Si that was getting too old to daily. Knowing my ex’s 2006 never had great AC, and living in central Florida, buying another 8th gen was a risky decision. I took a gamble since I loved the 8th gen so much. It was fine until the last two months, but the AC has shown its ugly side. This AC unit is probably fine in northern states, but definitely not in places like Arizona or Florida where you need all the help you can get.

Here are a few things you can try ASSUMING your AC is properly charged and serviced, and your car is tinted.

1. Clamp off your heater line or add a shutoff valve for the hot months:

No pics here. Vice grip stops coolant flow, which stops it from heating up your dash and/or vents.

I’ve learned this generation does not have a heater valve that shuts off coolant flow like the 88-2005 Civics did. I noticed when driving on the highway that my AC would get warmer while it was still running, and even worse when recirculation was turned off. This is a classic “reheat” condition, but could also mean my blend door is misbehaving. Either way, when I put a vice-grip on my heater line to stop the coolant flow the AC was super cold as long as the car was moving above 30mph, which brings me to my next point:

2. Seal the gap between your condenser and radiator to improve low-speed/idle performance

The idea is to force your fans to pull through the condenser.

When you have puller fans mounted to the radiator, the air has no choice but to flow through your radiator. The air then tends to flow AROUND the condenser and into the radiator, leaving you with warm air and swampass at stop lights. Honda is bad at this. Like REALLY bad. The 92-00 didn’t really have this issue because the radiator and condenser were side by side, not front/back. I immediately knew I was gonna have to seal it up because of how large the gap was.



Luckily, Lowe’s sells rolls of foam weatherstrip I used to seal gaps in several of my cars in the past. The left and right sides needed 3 layers.



Top and bottom normally need two layers, though the bottom of my condenser only needed one because the previous owner hit something 😊



I stuck my pieces of foam to eachother to get the desired gap, then to the condenser. They kind of flopped around until I remounted the condenser. Doing so pinches the foam in place.


It looks like crap but man it works.

After driving around town on a 98F day this past Sunday, I can verify the AC is FINALLY cold enough to be satisfied with at low speeds, high speeds, and in a drive-thru. It was cold from the vents in less than 2 minutes of driving and stayed cool. I honestly have no idea why this isn’t more common knowledge. It can be applied to almost any vehicle and costs $5 in materials.

For the long term I'm going to add a shutoff valve to the water line to use between April and October. For now it works great.

DISCLAIMER: If you clamp off your heater line your defroster and heater will be largely ineffective. Clamping can also stress the hose into leaking.

Your mileage may vary if you have an intercooler. Seal the condenser gaps at your own risk.

tl;dr Honda A/C is about as good as a GMC interior. Fight me

 

Lulz

Also do you have the auto climate control? I have found it can tend to cool the interior at the least aggressive rate possible. Taking it out of auto mode and forcing the AC on and dialing the temp to Lo will cause ice cubes to come out of the vents promptly. Auto mode probably leans towards fuel economy rather than comfort.

 

I do not. I have the regular climate control. Though I've heard bad stories on the newer Civics not cooling as well on eco mode if that's at all similar. Half-assing the AC just won't cut it when it's 95F and you can drink the humidity out of the air.

I kinda wish I had the energy to measure the vent temperature and low/high pressures before and after. Oh well.

 

ECO mode completely kills AC performance. Even turns off the blower motor. All to gain 1mpg. Some focus group came to the conclusion they would rather have swamp *** than spend an extra $0.39 at the pump.

 

When You unmounted the condenser did you disconnect the ac lines or did you have enough space to apply the weatherstrip?

 

Have you been able to tell what the difference is between max ac and normal? I swear it actually comes out warmer on max ac.

Thanks for all the detail, the summer is brutal here and my civic is black. Definitely need to seal up the front for better efficiency on mine.

 

Max ac is just a short cut button that turns on recirculation and ac. Its best to try and get as much heat out by driving with the windows down and just leaving the ac on for a bit after that turn on recirculation or max ac. This summer heat is killing me too in my black civic.

 

Really? This is true? I am only getting only 14 mpg now (and the A/C does not work well here in Naples FL). I got my 2015 Honda Civic either 3 or 4 years ago, at 118,000. I have never had it checked it. What do you recommend I do, meaning what should I check, and how, or should I change the coolant? What can help? I think it's working fine, just so, so hot here. The windows are tinted and I use windshield shades all the time. My Boxer hates my car...