AC still not working. any ideas.

so when I bought my truck (used) the AC didn't work. The compressor was bad. That was replaced and the AC worked. About a week later it quit blowing cold. so i took it back and they recharged the system. It blew ice cold for 3 days and now it's not working right again. As of right now, it's only blowing cold out of the drivers side vent. Any ideas what it could be. I suspect it has a leak somewhere. I was gonna take it in next week and see what they say, but wondered if there was something I could do in the mean time.

 

sounds like maybe the refrigerant is leaking?

 

does the AC light come on when you push the button?

 

yes it does. And stays on. when the compressor was not working, it would come on then the compressor was making a horrible noise, and the ac light would start blinking.

 

thats kind of what I am leaning towards. I think I am gonna take it to my own mechanic and pay to have it fixed. the shop that tried to fix it before apparently can't do it.

 

Sounds like they need to evacuate it and then put a vacuum on it and see if it holds. I'm guessing it won't. My first 05 and my brother in law's 05 both had the A/C compressors die when they were about 4 years old. My current truck (also an 05) had the compressor replaced once already. When I redid the A/C in my old fox mustang last year I brought it to 1 shop that didn't have a clue and talked to a few others who were also clueless. I wound up buying my own A/C gauges and vacuum pump and did all my own testing and charging. Still blows 38 degrees a year later.

 

It's blowing cold out of one vent, so you have cooling. That's not a refrigerant leak problem, because there isn't a way for low refrigerant to only affect one vent.

If the driver's side vent is blowing, but the others aren't, that's a problem with the dampers or their controls.

 

It did that last time too though. At first it just blew cold air out of the drivers vent, then after a day or two, it stopped blowing cold at all.

 

Negative Ghost rider.

 

This morning it's not blowing cold at all again out of any of the vents. Time to take it to a professional.

 

99% sure you have a leak in the system as some have suggested. Go to a qualified A/C shop and they will fix it.

 

Hmmm. Well, it seems to be puzzling me. The drivers vents blow out super cold air, but the middle passenger one is only mildly cold, and the passenger one is barely cold, if at all.
I never sit in the passenger seat, so I dont know if it's supposed to be that way or not. It should be blowing out the same temp air out of all the vents, right?

 

You have some servomotors that control the air movement.

 

If its blowing out cold in one I would bet the air mix servo's aren't working correctly. If you switch to heat does it come out the same temp in all the vents? Also have you tried switching to vent/floor mix? The servo might just be stuck a little, try moving the temp to hot>cold>hot a few times to possibly unstick it.

 

It's an air flow problem. Check to see if a damper is not closing or opening. Try to switch the vent settings. But to be sure I would check the pressures anyway. Remember now it's R-134a type freon. Check the pressures while it's cycling.

 

Well, I still think it's a leak. because now it doesn't blow cold at all AGAIN.
when I first get it back, it blows cold out of all the vents, then eventually only out of the drivers side, now not at all. the guy always says the freon is low when I bring it back. the heat blows super hot out of all the vents, and the fan blows the same temp out of all of them. And like I said, now it isn't blowing out cold at all. I would guess there is still a leak and the freon is low again. Where are the most common places for leaks. He replaced the O rings on the compressor last time.

Im trying to figure out how long to let the dealer's guy fix it for free, until i just say fuck it and take it either to my guy or the dealer.

 

If you go to an A/C shop, they're going to put UV dye in your refrigerant which turns into a horrible mess, then they're going to charge you a ridiculous amount of money for doing little to no work at all.


Go to home depot and buy a bottle of gas leak reactant soap bubbles. Then go to autozone and rent a set of gauges and buy a can of R-134a. Charge it per the instructions and spray it on all of the joints you can see with the soap bubbles. You should be able to locate the leak in less than 5 minutes, if you have one.

BAM, fixed for <$50

 

U can use a dye to trace a leak. Or look for oil stains around the refrigerant piping. Leaks can pop out of anywhere

 

Dye is horrible. Soap bubbles are cheaper, easier, and safer for the system.

 

ugh. I've never done anything AC related.