I have a 2000 durango with a 5.9 liter engine. The ac started leaking refigerant last year. I recharged the system and it worked fine the rest of the summer. So I figured if I had to throw a can in each year it was probably cheaper than taking it into a shop.

Well this year I recharge just like last year except this time the charge only held for a week or so. So then I decided to bring it to my mechanic. He told me that it was leaking from one of the valves and it was any easy fix. So he replaced it.

I was happy for about 2 months when it went out again. I'm not saying the guy didn't do a good job. I think he found one big leak and maybe overlooked a smaller one.

Anyway I have taken it upon myself to try and fix this problem and think i've discovered another one. I recharged the system again this time using a stopleak and plan to wait it out a couple of weeks and check the pressure. Now, with the system recharged, It blows cool not cold.
Today it was really hot and humid; 96F and 53% relative humidity or 78F dewpoint. With that ambient temp, my ac was blowing out of the vent at 74F idle and 70F while driving. My other truck was blowing out at 53F so I know it can do better.

Here are the things I've checked so far;

1. The compressor clutch engages and stays engaged while the ac is on.
2. The belts appear to be in good shape and taught.
3. Touched and felt the lines. The high side lines get hot and the low side lines get cool. Not cold but cool enough to sweat.
4. checked for leaves blocking air flow to the condenser. and it is free of debris.
5. Verified that I charged to the proper pressure relative to ambient temp.
6. Checked blender door by changing temp setting. It appears to be opperational.

I don't have the specialized pressure gauges to check the high and low side pressures. I believe buying them is my next step.

Does any one have any guidance for me on how to continue my diagnosis?
Is there any additional tests I can do before I buy these gauges? Any help is greatly appreciated.

Thanks in advance,
Dan

 

from here https://dodgeforum.com/forum/1st-gen...solutions.html

these measurements are made with the engine on and the engine held at 1500 rpm


IMO you need to get a set of gauges to hook up and get the pressures up to where they should be, it really sounds to me like your system is low on freon

keep in mind you should have this done professionally so that you get the correct amount (mass) of freon into the system.

 

Your evap is likely bad. That sucks actually.

Have a good shop stick a sniffer in the center vent to verify. When it beeps, be prepared to pull the dash. On the cheap, $600 in parts, $600 in labor.

Been there, done that. Still sucks.

IndyDurango

 

Thanks guys.

IndyDurango,

I Think you could be right about the evap unfortunatly. I do believe it is either leaking from there or close to it, as there is a sweet smell coming from the vents. especially when I move the temp control to heat then back to cold. Do you happen to know what specifically was wrong with yours? Could it just be the expansion valve? right now it is functioning just not a well as it should. Is a sweet smell freon from evap or anti-freeze leak from heating coil? Can't remember.

shrpshtr325,

I am pretty sure I have enough gas. I filled it up to 45 psi on the low side with the engine idling and the ac on max and the fan on max. The ambient temp was 94 at the time.
Does the relative humidity also effect what the pressure should read? If so than I did not factor that in.
I will go buy the gauges later today and update you guys with the results.

Once again, thaks to both of you for your help.

 

The maple smell is antifreeze from the heater core.

The expansion valve is firewall mounted, underhood so you would smell nothing from there.

IMHO, you have two issues. Fortunately, you swap them both at the same service anyways.

When you pull the dash, replace the evap, the heater core and the fan. Make sure they properly seal the air box back up exactly as it was when they took it apart. It will be noisy as hell when the fan is running if they don't.

What happens is the evap and core simply break down, get pin holes in them and leak. Nothing you can do really other than replacing them.

It is fairly a biattch to DIY so be prepared for the entire weekend to R&R or prepared to pay for the related costs.

IndyDurango