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1990 Honda Accord high vent temps

cody2979 on Tue June 03, 2008 8:42 PM User is offline

Year: 1990
Make: Honda
Model: Accord
Engine Size: 2.2
Refrigerant Type: R134a
Ambient Temp: 95
Pressure Low: ??
Pressure High: ??
Country of Origin: United States

I've had this car for a while and the A/C has slowly stopped working well. It has been converted some time ago to R134a at a qualified shop. It has been several years since the last charge and it is now working, but not working well. I can tell that the compressor is kicking in and the vent temperatures drop slightly, but not near enough to stay cool. I have a set of Madden gauges with R134a couplers like the ones in this ebay auction # 350065989958.

I was trying to start diagnosing the problem. The low side hose went on with no problems, but the high side port doesn't seem to couple correctly and I'm losing gas each time I try to connect the coupler. I am wondering if I have the correct coupler because after several attemps I still haven't got the quick coupler to snap on.

The high side port is in a really bad spot and the line isn't supported well either, and I'm sure that this is contributing to my problem.

Any suggestions? Is this the correct coupler?

mk378 on Tue June 03, 2008 8:58 PM User is offline

What kind of adapter is on the port? If it's the aluminum Interdynamics one that uses the stock shrader valve, try a steel one like AMA sells (you can also find them in local parts stores, just not the "discount" chain ones). Some of the cheap gauge sets just aren't made right, the tolerance means they may work on some cars but not others.

Chick on Tue June 03, 2008 9:18 PM User is offlineView users profile

Just to add, try holding the line under the port while you try to snap it on. (the line is very slim so don't bend it) Make sure you have both a high and low side adaptor..Had a guy come in once with two high side adaptors on his gauges set...

Email: Chick


Freedoms just another word for nothing left to lose

cody2979 on Tue June 03, 2008 10:19 PM User is offline

Thanks guys. Okay, I did finally get the quick coupler to fit. I had to replace the R12/R134a adapter that was on the high side gauge port. The ambient temp. was 88F and the system was like 10psi on the low side and about 100psi on the high side...extremely low, but I'm not sure how much was attributed to the fact that I leaked off a ton trying to get the coupler to fit.

Do I need to evacuate the system realizing it's so low, or is it worth trying to simply recharge with 134a? I don't have a vacuum pump but, if it's necessary I can invest in one.

Chick on Wed June 04, 2008 6:31 AM User is offlineView users profile

You can try topping the system off first, Be sure no air gets into the system. Charge slowley until you feel the return (suction) line to the compressor is cold..Waiting a minute or so to let the system equalize, once it's cold, your high side should be around 2.2 to 2.5 times the ambient temp "as a guide".. Since it's a retrofit, you can't go by weight. Each system will be different...Hope this helps..

If you want a GOOD vacuum pump, Check out Mastercool pumps. Prices are right...

Email: Chick


Freedoms just another word for nothing left to lose

cody2979 on Wed June 04, 2008 7:15 AM User is offline

Thanks again. I'll give that a try.

NickD on Wed June 04, 2008 9:59 AM User is offline

Ha, screw Al Gore, the ozone layer, and the penguins on these cars, like sticking with R-12, using only Honda oil, and checking refrigerant level is quicker than checking the engine oil level. With AC on, doors open, blower at max in a warm 85*F plus day, rev the engine and check the sight glass for bubbles, can also gauge leaks by checking it a couple of weeks later under the same conditions to learn if you have more bubbles. These systems are marginal anyway and work much better with R-12, only takes a couple of cans to fill the system from empty. Just my worthless opinion.

cody2979 on Thu June 05, 2008 7:48 PM User is offline

Thanks Nick. I tend to agree. The car I'm driving was converted to 134a a while back and has never cooled the same since. I was finally able to get the hoses and fittings I needed to charge the system up a little. Here is a little info on the system maybe you can help me understand what is going on:

90deg ambient temp - car in the shade
Fan - full on
windows open
max. cool
High side - 90psi (before charge)
Low side - 10psi (before charge)
vent temps basically ambient

after charge:
high side - 160psi
low side - 28-30psi
vent temps - 70F(60F on the outside vent)

I couldn't get even a single can of refrigerant in it before it stopped accepting coolant.

The site glass is still showing pulsations or what you call bubbles I'm assuming.

What do you guys think. Not sure what to do from here. I thought it would take more coolant than it did.

Chick on Thu June 05, 2008 8:21 PM User is offlineView users profile

Your high side should be around 200-225psi at 90 degrees (Roughly) but being it's still low, you need to know why it's not going in? You may have to recover and recharge properly if you don't know how much is in there.. The outside temp is much higher than the low side pressure, meaning it should be forcing the refrigerant into the system..I'd check the connection to the low side again..Just a thought..If you do get it to go in, charge slowly until the suction line is cold back to the compressor, and watch the high side..But you are still undercharged..

PS: Don't pay to much attention to the sight glass, as it was designed for the R12 that was originally in it..R134a seldom clears the sight glass when retrofitted,

Email: Chick


Freedoms just another word for nothing left to lose

cody2979 on Thu June 05, 2008 8:57 PM User is offline

This is the first time I've charged a system, so I'm not sure I've done it all properly. I was pretty careful not to introduce any air into the system. I was checking the suction line to the compressor while opening the valve to introduce coolant into the system. The line never did cool down and was always just barely warm to the touch. Eventually, I had the valve on the can wide open and the valve on the low side of the manifold wide open and I wasn't getting any change in the system pressures.

I can tell that there is still liquid in the can. Could the system be full and still only show 160psi on the high side?

I will check my low side connection as you suggest.

mk378 on Thu June 05, 2008 9:28 PM User is offline

Your system was nearly empty when you started; it is still undercharged. It may need more than one can.

Always open the can tapper valve fully. Control flow with the low side valve on the manifold.

The can will get real cold when you do that. This reduces the pressure inside the can until it is only charging very slowly. Your options are:

*wait a long time
*rev up the engine (system low side will drop)
*warm up the can in some warm water (no open flames, etc)
*charge as liquid

Charging as liquid means you turn the can upside down and open the valve SLIGHTLY. Do not open the valve wide. It will charge much faster as liquid.

cody2979 on Fri June 06, 2008 12:53 PM User is offline

Hey that worked great! Initially, after the can got low enough, the pressure in the R134a can hit some equilibrium point with the low side of the system and it wasn't flowing. I read your message and decided to try again.

I took a small tub of hot water outside with me. I started the car, opened the valve to the can, and opened the valve a little on the manifold and the gas still wasn't flowing. So, I dipped the can into the hot water and immediately I started getting flow into the low side and the pressure started rising on the low side. I also idled the car up slightly to bring the pressure on the low side down.

I was able to get 2 full cans in the system and my vent temps went down to 55F where they were 70F before. I completely emptied 2 cans of refrigerant into the system and only stopped because we had a storm coming in. Should I try to top the system off with a 3rd can?

Here are the stats:

Ambient 80-85F
Fan- Full ON
High side - 190-200psi
Low side - 35psi

mk378 on Fri June 06, 2008 4:44 PM User is offline

If those numbers are at idle it's working pretty good. Try it while driving, of it gets cold don't mess with it.

Rated R-12 capacity is 32 oz. You don't want to go over that in any case. So maybe part of a third can could be used.

cody2979 on Fri June 06, 2008 8:08 PM User is offline

I checked my pressures again today since it was pretty warm.

Ambient - 90-95F
High side - 200-210psi
Low side - 50-60psi
vent temps - 65-70F @ idle
Fan full ON, windows down

The low side seems pretty I need to do anything to bring the low side down or will 50psi be okay?

Thanks again guys...couldn't have done it without your help...and the adapter I bought from

TRB on Sat June 07, 2008 2:40 PM User is offlineView users profile

Those pressures at idle or 1500RPM? What are the pressures at 1500RPM?


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