DODGE RAM FORUM - Ram Forums and Owners Club! - Dodge Truck Forum

DODGE RAM FORUM - Ram Forums and Owners Club! - Dodge Truck Forum (
-   Heating & Cooling (
-   -   A/C problem???????? (

brondondolon 07-18-2013 07:18 PM

A/C problem????????
Hey guys its been a while since ive been on here, 4 years or so, but i sold my 98 ram and now i own a 09 that is having an A/C problem. after taking a trip to the dealership today i found out my warranty has expired so now im on my own.

here's the problem. the day i bought the truck it had a funny smell coming out of the a/c vents, it smelled like a urinal cake, so i took it in and had them check it out. they apparently did tests and found it was the cabin filter. however when i got the truck back the a/c has been intermittent. especially when its above 90 deg outside... i can hear the clutch turning off and on at idle as well. but what should i check or has any one had a similar problem? also if needed i can check how many lbs of R-134a are currently in there.

09 ram 5.7L automatic 2wd 49k miles

thanks guys i truly appreciate:smileup:

astroman54 07-18-2013 07:40 PM

The only way I know of to check how much R-134a is in the system is by pressure. They use a scale on the filling bottle to know how much they have put into the system, so the # of lbs comes from there.

It sounds like you need to top off the R-134a in your system to the point where it doesn't cycle the compressor clutch. It sounds to me like it's pumping until the low refridgerent switch turns the system off, and when it builds up again, it lets it start again.


Simple guy 07-18-2013 09:20 PM

You can buy a R-134a recharge kit. I suggest one that has a pressure gauge with an adjustment for ambient temperature. Follow directions from the kit.

Edit: Side note, an overcharged system is not a colder system. It can even cause seal failure; typically at the compressor.

astroman54 07-19-2013 10:29 AM

Yes.. if you overcharge the system, then there isn't enough of a differential in pressures between the high and low sides of the A/C system and the it will not blow as cold as it would with a properly filled system. A low pressure gauge while installing is better than none. Without a pressure gauge, I've added just enough to keep the low pressure switch from kicking in and making the compressor cut out. If you use that method then give it a good couple of minutes of running before deciding it's had enough for all of the pressures to equalize in the system.. It may run ok a while, but when it equalizes, it may start cutting out again.


brondondolon 07-19-2013 03:43 PM

how many lbs should be in there? after reading on the internet yesterday i read our compressors are very sensitive and will only work with an almost exact lb but i couldnt find what the lbs should be right now im in the 70lbs range then it jumps to 100 when cycling which is pretty high.

astroman54 07-19-2013 07:22 PM

Ahh.. You're talking PSI, not lbs.. When the compressor starts, the low pressure side should drop and the high pressure readings should go up.. The pressures need to correlated to the ambient temperature.. See the link here for a better explaination and PSI chart.


astroman54 07-19-2013 07:27 PM

I should add that many that service A/C's will pull all of the refrigerant out of the system and put new in, and charge the system by weight (lbs) not by pressure (PSI). If I'm not mistaken, Chrysler's specs are in weight for an empty fill.. The tech will put the cylinder that they are filling from on a weight scale and cut off when it is lighter by the specific amount.


All times are GMT -4. The time now is 10:52 PM.

Powered by vBulletin® Version 3.8.9
Copyright ©2000 - 2015, vBulletin Solutions, Inc.
= Copyright a Network Site =Ad Management by RedTyger