AC Repair

KO1

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#1
Make
Chrysler
Model
Town & Country
Year
2010
Miles
134,000
Engine
V6 4.0L
I am having a issue that I cannot find any info on surfing the internet. Similar-but not my situation. I have a 2010 Chrysler Town and Country Touring 4.0L and my freon became low. Discovered a small leak at a connection point on one of the rear lines that I will be repairing but want to make sure I can resolve the other issue first before spending time and money on the leak.
When adding freon it will hold a charge for several days-enough to blow cold air. Problem I can't figure out is while monitoring the manifold gage (before and after adding freon) the low and high side will rise, then the fan turns on in front of the condenser and then both pressures lower. Then the fan turns off and both pressures rise again. This whole process takes about 40 seconds and it never stops. Even when I added freon to the proper PSI (for the current ambient temperature at the time) both the low and high side continue to rise and fall about every 40 seconds. The pressures that it would rise and lower to were:
low side would rise to about 35 and the high side to about 250, then the low side would lower to about 22 and the high side to about 150.
Any help would be appreciated.
 
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#2
AC normally cycle on and off.
The compressor cycles on - HIGH builds and low falls, when the low drops to a predetermined reading it will kick off, waits for the low to once again reach PSI IIRC @ 40psi the system turns on and repeats....
An issue would be if the high pressure rose to high it would kick out- likely set a code. All pressures are monitored by PCM so check codes

Do NOT use a refrigerant with a sealant !!
Fix the leak so oil quantity does not become a concern.


ANAL I know BUT you do NOT use freon you have SUVA R134a
 

KO1

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#3
If my check engine light doesn't come on could there still be codes generated to retrieve?
 

billr

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#4
Yes. And be sure to use a scanner that can read all codes, not just the basic OBD2 ones.
 

KO1

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Yes. And be sure to use a scanner that can read all codes, not just the basic OBD2 ones.
Appreciate your help. What am I looking for in a scanner that tells me its not just a OB2 scanner?
 

billr

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#6
For immediate purposes, go to your FLAPS to get it read, and confirm that the scanner they use will read all codes. You are looking for "extended codes" or "manufacturer-specific codes".

Long term, I think there are threads/articles in these forums that discuss features on various brands of scanners. I'll take a peek for such, or somebody else will post more current info.
 
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#7
every time you move key start vehicle the CEL should come on for @2 seconds then go out.

Scans are often FREE at most auto part stores, auto zone advance auto, Orielys - FREE
 

nickb2

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#8
What am I looking for in a scanner that tells me its not just a OB2 scanner?
For cheap, you could buy this little gem. But remember, it will only do chrysler products. But with this, you can do it all. Except reflashing, for that you will need an additional interface with j2534 protocal. Those to can be had cheap from china. But remember, with these clones it is hit and miss sometimes, you may have to return one or two.

It is a china clone, even though one of the pictures says it is made in usa, don't beleive that. but I have heard good reviews. You can get a DRBIII emulator, just google it. Forum rules prevent me from giving pirated info. But if you look enough you will find it. But the provided witech software is more than enough.

For 200$, this thing rocks. Sucks that it is based on a elm327 platform, but proprietary stuff usually costs. The elm 327 dongle @ 15$ on e bay are very limited.

Here is a link. http://www.uobdii.com/wholesale/witech-micropod-2-diagnostic-tool-for-chrysler.html
 
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KO1

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For cheap, you could buy this little gem. But remember, it will only do chrysler products. But with this, you can do it all. Except reflashing, for that you will need an additional interface with j2534 protocal. Those to can be had cheap from china. But remember, with these clones it is hit and miss sometimes, you may have to return one or two.

It is a china clone, even though one of the pictures says it is made in usa, don't beleive that. but I have heard good reviews. You can get a DRBIII emulator, just google it. Forum rules prevent me from giving pirated info. But if you look enough you will find it. But the provided witech software is more than enough.

For 200$, this thing rocks. Sucks that it is based on a elm327 platform, but proprietary stuff usually costs. The elm 327 dongle @ 15$ on e bay are very limited.

Here is a link. http://www.uobdii.com/wholesale/witech-micropod-2-diagnostic-tool-for-chrysler.html
Thanks for all your input. The issue that brought me to having low freon was a slow leak at a connection point on a rear line right before the rear evaporator. It Screenshot_2018-07-28-18-48-10~2.png Screenshot_2018-07-28-19-58-32~2.png leaks behind the big nut and at the threads. Included picture with arrows showing points of leak. I took it apart and it had one o-ring in it. I purchased the whole AC system set of o-rings for my vehicle and picked out the exact one that matched the one I took off. Replaced it and tightened it back up. Recharged AC and it still leaked.
Read online there could be some crud in there so I took it apart and lightly sanded the inside surface of the fitting, then rubbed some brake cleaner on the inside of fitting. I then put another new o-ring on there. Recharged AC and it still leaked.
Then thinking I may have overtightened it and distorted the o-ring I figured I would loosen the fitting to the point where I could hand tighten it, then turn it a quarter of a turn at a time and check for leaks until I found just the right torque to compress the o-ring without smashing it. Ended up tightening it to the point that it couldn't be tightened anymore and it never stopped leaking.
Wanted to see if anyone had any suggestions of what could be going on. If it can't be figured out I am going to cut that connection out and replace it with a Dorman Line Splice For Aluminum Lines (which is the second picture I included).
 

nickb2

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#10
If it can't be figured out I am going to cut that connection out and replace it with a Dorman Line Splice For Aluminum Lines (which is the second picture I included).
From reading what you wrote, this sounds like the best way to go. I weigh only 155 pounds and my hands are not to fat. But stuff like this happens once in a while. Some things just wont seal no matter if my slender body tightens it like if I weighed 280pnds.
 

nickb2

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#11
This sort of thing I used to encounter very often when I was an apprentice and my ego would get in the way. Mostly what happened back then, some old fart would come by and redo my job, 5 mins later all was ok.

Now I am that old fart. Experience cannot be bought with a high end tool box and the marriage contract that comes with it. The new apprentice at work is way over pnds, doens't know yet how to operate a proper torch set, big fat hands and can't fit under a dash board. Basically just cries when things don't go his way. Bad attitude and way to much effort in eating than working.
 

nickb2

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#12
Don't even get me started on apprentices and their f ing smart phones.

Btw, good on you to notice that that ac leak was probably a distorted union due to some jack off going Arnold Schwarzenegger on those threads. Because 90% of the time shyte like that happens, some idiot came blue in the face thinking that would stop the leak. Sadly, life just isn't like that.
 

jigfeett

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#14
K, did you get it fixed?
I had a random issue with A/C and ended up replacing 1st, low pressure switch, 2nd orifice tube-accumulator & condenser
( The dealer stated condenser and accumulator was clogged) {Dealer stated low side was high and high side was low}
3rd replaced heater head unit ( found burned marks on circuit board)
4th and last replaced compressor. Nothing fixed the issue until I replaced the compressor but the system is virtually new and sends cold air to the cabin at as low as 37°

Just my personal thought if a vehicle has 150K or more the best way to go is replace as much as you can afford but always fix the leaks first.
Thanks