Need AC support on 2000 accord

[Voltmaster]

Howdy,

My 2000 accord's AC system is really jacked up. IT does all kind of wierd things ,

Some days it works perfectly , somedays not.

Only time it works 100% on level 3 ( out of 4 ) is going "speed limit" on freeway. Even after car has been on for 15 min , if it goes on idle ( waiting for someone outside ) it turns warm sometimes ( not all! id say about 60% ) after about 3 min.

Have checked the freon , its running nearly at maximum safetly pressure. No leak stays in same pressure more or less every day.


Condenser is aftermarket , fans are ok , compressor is ok. My car didnt have caps on the ports so I got some from autozone ( I was thinking maybe air has gotten in and need to have a mechanic vacuum and charge it. )

The hose going from compressor , its ice cold. I mean if you hold it for 10 seconds you gonna feel like you going to freeze your hands off.


Condenser is clean,

I cant figure this one out. Only thing I notice is that engine makes really weird sound going into sub 700rpm idle , it sounds more of electronic noise than mechanical ( i was thinking maybe blower? ), also the car almost wants to stall form time to time rmp drops to 400 before reving back up to 850ish when idling. Id say it happens once or twice a week.

Belts look good and not worn.

Please help me troubleshoot this , going to be 100+ soon in LA.

Another note :

Two diffrent brands of 134a was used , is this bad?

 

[robshelton]

Sticking/hanging expansion valve

 

[rjundi]

I doubt this is the issue given the symptoms however I was getting intermitent AC in my Acura MDX and a known issue with mine is faulty AC Clutch Relay(in fusebox). It cost a paltry $6 from the dealer albeit the same part that is common failure. They have a revised part but for $30 hardly worth it for blind guess.

Sidenote Honda parts guy recommended using cheap part to me after consulting with shop guys on his own doing. Really nice dealer at least in parts! Dealerships are not always stealerships.

 

[Donald]

Did you measure high pressure? The caps are just to keep the valve clean, not to prevent a loss of freon. Did you base your high pressure on ambient temp? There are charts.

 

[Chris142]

What are the high side pressure readings? W/o that nobody can help

 

[Chris142]

Donald. The caps are the primary seal. Stupid I know.

 

[Donald]

Originally Posted By: Chris142
Donald. The caps are the primary seal. Stupid I know.


They are just pushed on right? How can they be a primary seal?

 

[Chris142]

They are threaded and have a rubber seal inside.

 

[Chris142]

Are the cooling fans coming on with the ac?

 

[Fleetmon]

it sounds to me like it's overcharged.....like others asked, what is the high pressure? The pressure being at 'max".....what does that mean since there is no such term in ac? It sounds as if you're reading from one of the cheap kit gauges that are bought at wm and auto parts stores.....they tell you very little.

 

[Tegger]

Originally Posted By: Chris142
Donald. The caps are the primary seal. Stupid I know.

I'm no A/C expert by any stretch, but I find it impossible to believe that the threaded cap is the primary seal. I'll bet the primary seal is the Schrader-like valve that's hidden under the cap, and that the rubber seal on the cap is meant as a backup in case there's leakage past the Schrader-like valve.

If the threaded cap was the primary seal, you would have released all the refrigerant while taking it off to look at the rubber O-ring inside the cap.

 

[spackard]

Why would the suction line of the compressor be so cold, yet warm air is coming out the vents (after blowing across the evaporator)?

Agreed that pressure/temperature/humidity chart works, but in absence of that it sounds like a blender door motor is broken. I had a problem with my wife's '03 TL-S with fully automatic climate control. There's a motor with a white shaft visible on the passenger side. It broke, and the M-HVAC blew hot air. It's a DIY fix.
Check into your system to see if it has a similar setup. (I'm a hobbiest, not a pro.)

As far as the engine making wired sounds below 700rpm, maybe you have another problem and the engine is trying anything to avoid stalling.

 

[JC1]

You'll need to check your pressures with a set of AC manifold gauges like the ones from harbour freight.

http://www.harborfreight.com/a-c-manifold-gauge-set-92649.html

Like previously mentioned if you are overcharged, the system won't work properly, it's trying to protect itself. Likewise when it's too low on R134a it usually won't blow cold enough.

Once you know the R134a level is correct then you should start looking at other things.

Regards, JC.

 

[SwampSurvivor]

I would think it's too low. If it's overcharged, it would build pressure too quickly running down the highway and not cool.

However, if it's low, it would only build pressure and work when the engine is spinning it fast.

 

[Chris142]

The Schrader valves are only there to hold the refrigerant in long enough to get the caps on. Is the heater putting hot water into the heater core in making the air warm inside? Heater valve leaking? Blend door not closing? Lots of things will make it hot inside other than being low on refrigerant

 

[Tegger]

Originally Posted By: Chris142
The Schrader valves are only there to hold the refrigerant in long enough to get the caps on.

Really. Is that also how Schrader valves work when they're used on tires?

And if that's so, then how come so many other cars have plain plastic caps with no rubber gaskets covering the Schrader valves?

 

[01rangerxl]

I think Chris is right...when I take the caps off my A/C system, there is a faint hissing noise for a second and the threaded part of the cap which presses down on the valve has some refrigerant residue on it. Beyond the o-rings, there is no residue. It seems like the valve is just there to aid in adding/removing refrigerant, and once the caps are on they do the real sealing. These caps aren't like tire valve stem caps...the threaded center piece goes down into the valve and is surrounded by the o-ring.

 

[Fleetmon]

The caps are only to keep dirt out they are not meant to seal.....if you hear a hiss when you remove the cap, your schrader valve is bad.

I meant I thought the ac was cutting off on high pressure. I was thinking a possible overcharge if liquid refrigerant is backing up, i.e. not evaporating. A blend door is a good possibility too.

 

[Tegger]

Originally Posted By: Fleetmon
The caps are only to keep dirt out they are not meant to seal.....if you hear a hiss when you remove the cap, your schrader valve is bad.

No Honda or Toyota A/C system I have ever seen uses the caps as the primary seal for the ports.
Every Honda and Toyota system I have ever seen uses the Schrader valves for primary sealing (different sizes for high and low).
Schrader valves do NOT leak unless defective or dirty.

Maybe Ford does it differently, I don't know. But we're talking about a Honda here, not a Ford.

 

[jrustles]

Originally Posted By: Tegger
Originally Posted By: Fleetmon
The caps are only to keep dirt out they are not meant to seal.....if you hear a hiss when you remove the cap, your schrader valve is bad.

No Honda or Toyota A/C system I have ever seen uses the caps as the primary seal for the ports.
Every Honda and Toyota system I have ever seen uses the Schrader valves for primary sealing (different sizes for high and low).
Schrader valves do NOT leak unless defective or dirty.

Maybe Ford does it differently, I don't know. But we're talking about a Honda here, not a Ford.


you're right. no screw-on cap on any refrigeration system is a "primary seal" where "primary" means first pressure seal, not "primary" as in first defense against external contamination.

it does sound overcharged.

please describe the compressor duty cycle to us.

At idle, is it frequent on/off, more off than on, more on than off, or on all the time?