# Evaporator Core/ AC question **URL:** \ **Category:** Maintenance/Repairs\ **Tags:** kia, rio\ **Created:** [March 23, 2017, 7:25pm UTC](https://community.cartalk.com/t/evaporator-core-ac-question/102019 "2017-03-23T19:25:11Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![paulyj](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/paulyj/32/6879_2.png) [@paulyj](https://community.cartalk.com/u/paulyj)\ **Post date:** [March 23, 2017, 7:25pm UTC](https://community.cartalk.com/t/evaporator-core-ac-question/102019/1 "2017-03-23T19:25:11Z")
Hi there:), new to cartalk When the AC went out in my car, the clutch engaged so i know it had refrigerant. i hooked up one of those gauges that attaches to a can of refrigerant. The gauge read that the system was overcharged so i didnt add anymore.then i used a set of manifold gauges, the low side had a high reading, and the high side had a low reading. After recovering the refrigerant i checked the expansion valve and evaporator core . The Expansion valve looked fine (but honestly i wouldnt know if it was broken or not), but the evaporator looked pretty dirty. QUESTION : is there a way to clean an evaporator core , and if not what else could be causing the AC to fail? Thanks:) Also in the picture i attached, what is that wire connected to? is it a sensor? if so, could that be a cause of my AC not working? ![](https://global.discourse-cdn.com/cartalk/original/2X/7/7475873d34cf42dfdf05760b2a1f6cd157662f4b.jpg) ---
**Author:** ![insightful](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/insightful/32/2732_2.png) [@insightful](https://community.cartalk.com/u/insightful)\ **Post date:** [March 24, 2017, 1:21am UTC](https://community.cartalk.com/t/evaporator-core-ac-question/102019/2 "2017-03-24T01:21:20Z")
> [@pauldjuarez](#): > > i used a set of manifold gauges, the low side had a high reading, and the high side had a low reading. What were the readings? > [@pauldjuarez](#): > > what is that wire connected to? is it a sensor? if so, could that be a cause of my AC not working? I believe the wire running along near the top of the evap core is the thermistor that senses freezing conditions and turns the compressor off. I don’t think it would cause your problem. ---
**Author:** ![asemaster](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@asemaster](https://community.cartalk.com/u/asemaster)\ **Post date:** [March 24, 2017, 2:46am UTC](https://community.cartalk.com/t/evaporator-core-ac-question/102019/3 "2017-03-24T02:46:12Z")
> [@pauldjuarez](#): > > then i used a set of manifold gauges, the low side had a high reading, and the high side had a low reading. Sounds like a failed compressor to me. ---
**Author:** ![paulyj](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/paulyj/32/6879_2.png) [@paulyj](https://community.cartalk.com/u/paulyj)\ **Post date:** [March 24, 2017, 10:05am UTC](https://community.cartalk.com/t/evaporator-core-ac-question/102019/4 "2017-03-24T10:05:58Z")
dont remember the exact numbers but the low side was at around 60 or 70 psi and the high side was at like 80 or 85 psi ---
**Author:** ![asemaster](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@asemaster](https://community.cartalk.com/u/asemaster)\ **Post date:** [March 24, 2017, 1:38pm UTC](https://community.cartalk.com/t/evaporator-core-ac-question/102019/5 "2017-03-24T13:38:32Z")
If the compressor clutch is engaged and those are your pressure readings, the system is slightly low on charge and your compressor has failed. ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [March 24, 2017, 2:00pm UTC](https://community.cartalk.com/t/evaporator-core-ac-question/102019/6 "2017-03-24T14:00:27Z")
You are now in the “take it to an expert” area. Find a good a/c shop in you area and have them diagnosis it.