Diagnose AC no cool

[anamealreadyinuse]

First time posting, glad to have found you guys. I have a 2003 V6 with about 100,000 miles. Last year I added coolant when the air conditioning stopped blowing cool air, that worked great. I purchased some additional coolant when the same problem reocurred about a week ago and it lasted about a week. Do you have any advice for diagnosing the problem? I'd like to repair the air conditioning myself. I noticed the individual parts for a condensor for example is much cheaper than a mechanic repairing it?

 

[iBison]

First time posting, glad to have found you guys. I have a 2003 V6 with about 100,000 miles. Last year I added coolant when the air conditioning stopped blowing cool air, that worked great. I purchased some additional coolant when the same problem reocurred about a week ago and it lasted about a week. Do you have any advice for diagnosing the problem? I'd like to repair the air conditioning myself. I noticed the individual parts for a condensor for example is much cheaper than a mechanic repairing it?

I'd take it to a shop. They will put dye in it that can be seen with a UV light so they can find the leak. Make sure they keep looking when the find it in case there is more than one. I had my grand prix in for this a few years ago, the shop replaced a valve, then after the problem resurface days later they said the condensor was leaking and was around 300 just for the part. We got one at the junkyard for $20.

 

[HokieRunner]

It sounds like you have a refrigerant leak. If you want to diagnosis and repair it yourself, hop on YouTube and watch some videos on how to find a leak. You'll also need tools (pressure gauges, dye for finding the leak, vacuum for draining, etc).

And yes, it's always cheaper to just buy the part because a mechanic charges for their labor, so you'll have to decide whether you want to invest the time and money in tools and learning how to do it. I'd definitely watch a few how to videos to get an idea what it involves.

If It were me, I'd at least get it professionally diagnosed and make the call from there.

 

[preacher35]

If your mechanic DOES NOT find the leak in the engine compartment, then you need to consider whether or not you have an evaporator leak, which is behind the dash, against the firewall.

 

[anamealreadyinuse]

Ac

Thanks guys, I'll definitely have a mechanic at least diagnose it. The condenser appears to be pretty straight forward but maybe that will translate to a cheap(er) repair and I can just be done with it.

I love this vehicle, it's the best I've ever owned and I plan and keeping her for awhile. Glad to have found such a specific forum.

 

[earthrealm]

4runners are known to develop the evaporator leak, the evap is behind the dash....my a/c is still acting up..and am beginning to lean towards an evap leak.....a/c works well for about 2months...then it needs a refill again

 

[iBison]

If you need to reach the condenser or something make sure you have the refridgerant evacuated first.

 

[preacher35]

4runners are known to develop the evaporator leak, the evap is behind the dash....my a/c is still acting up..and am beginning to lean towards an evap leak.....a/c works well for about 2months...then it needs a refill again

Yup, mine did the exact same thing. Cold air for about 2 months, then warm air out of the driver vent while cool air out the passenger for a day or two, then nothing. Freon recharge. The "2 months" then became 6 weeks, then 1 month, then a week. Summertime here in Southeast Texas motivated me to just bite the bullet, and drop the thousand dollars required to replace the evaporator. That was a hard one to swallow.

 

[anamealreadyinuse]

Evap

You really have to question the placement of the evap behind the dash as I'd imagine AC is a common repair, why not figure out a more easily accessible area to stow it?

 

[preacher35]

You really have to question the placement of the evap behind the dash as I'd imagine AC is a common repair, why not figure out a more easily accessible area to stow it?

I asked this question as well, but [MENTION=66389]BlackWorksInc[/MENTION] (Toyota tech) stated that this is now a common place for auto manufacturers to put the evaporator. And all of these years, I thought that the most expensive HVAC item to replace would be the compressor.

 

[BlackWorksInc]

The placement of the EVAP core has been the same for a couple decades now. Some GMs had them externally in a clamshell box on the firewall, but those were just as much work to take out/reseal (my '93 S10 Blazer was a pain when I decided to clean it out and reseal it.)

Its about getting the cold air fastest to you and since the heater core is already in there, they just add blend air doors and some ducting and now the whole HVAC assembly is under the dash.

 

[nevada]

The placement of the EVAP core has been the same for a couple decades now. Some GMs had them externally in a clamshell box on the firewall, but those were just as much work to take out/reseal (my '93 S10 Blazer was a pain when I decided to clean it out and reseal it.)

Its about getting the cold air fastest to you and since the heater core is already in there, they just add blend air doors and some ducting and now the whole HVAC assembly is under the dash.

yes, it really is the best placement.

altho, they should be able to come up with easier access. both for it, and the heater core.

some vehicles require pulling the entire dash out 6-10 hours at times.
others, there is an access door, 15 minutes tops.

theres no reason they cant all be designed that way.

 

[4RBob]

My issue (and I have seen others on here too) was a leaking drier plug. The drier is on the side of the condenser. I paid Firestone ~$150 for evac/vacuum/recharge job. Firestone evac'd the AC system, I picked up the 4R to change out the drier kit (desiccant bag/plug with o-ring). However, the plug was too corroded and we could not get it out without f'ing up the threads of the drier. Ended up returning that kit and getting the whole condenser (drier included). BTW - Autozone's condenser does not include the two o-rings needed for the job. Bought a AC o-ring pack. Also had to buy a few screws as the old ones were corroded and broke off during removal of old condenser. Then went back to Firestone and had them do vacuum/recharge.

This was a couple of weeks ago, seems to be working fine so far.

 

[earthrealm]

[MENTION=11004]4RBob[/MENTION] , can you please show us a pic of the drier/plug, if possible...is it easily accesible?

 

[4RBob]

[MENTION=11004]4RBob[/MENTION] , can you please show us a pic of the drier/plug, if possible...is it easily accesible?

This is not mine, searched for it as I remember seeing it before when I was searching on A/C issues. Mine was actually much more wet. The drier is on the side of (part of) condenser (radiator type thing behind the front grill).

 

[earthrealm]

AM ASSUMING ITS THE PART I CIRCLED IN RED?.....u mentioned wet, so if its leaking from there, that area would be a lil wet?..or u can feel freon escaping if u put ur hand there.......or it must be via uv light etc?

 

[4RBob]

AM ASSUMING ITS THE PART I CIRCLED IN RED?.....u mentioned wet, so if its leaking from there, that area would be a lil wet?..or u can feel freon escaping if u put ur hand there.......or it must be via uv light etc?

Yes, that's the part. It was very wet on mine. It was also a little damp at the bottom connection on the other side of the condenser. The condenser had a ton of little pebbles in it and was a bit dinged up.

I should back up a little bit. We had tried adding some freon (using gauges) before, but it only helped for less than a week. I saw a $10 coupon for Firestone to do an A/C check. I already knew about the wet drier before this. Firestone called and said they couldn't find anything and said it was blowing "pretty good" at 50F. I highly doubt it was even that cool. I mentioned the drier to them and they said "oh yeah, we can try changing that". They were going to change it themselves, but called me to tell me they were worried about damaging the drier/condenser when taking out that plug (I mentioned before was impossible because of corrosion). I told them I would change it or the whole condenser myself and they can do the evac/vac/recharge. As I mentioned before, ended up replacing the whole condenser.

Before the repairs/recharge were done, I noticed the compressor was cycling on and off like crazy (1-2 seconds on, 1-2 seconds off several times then 30 seconds on once in a while). I also did the sight glass test (you can search for a pdf on this on the forum). There was nothing going on in the sight glass at all. AFTER the work was done, when you turn OFF the A/C, you see some bubbles/foaming then it clears up. This is correct according to that test. The compressor doesn't cycle like crazy any more either.

I should say this is appearing to work for us right now, but it hasn't been that long so I can't say for sure if it is THE fix. I figured it was wet and it was worth trying as it is one of the cheapest/easiest components of the AC system and it is kind of a wear and tear item getting beat up in the front there.

 

[anamealreadyinuse]

2 Years Later

2 Years later and I finally had the evap core replaced along with a few other items to the tune of 1K. I used the A/C Leak Seal instead of the Freon with Sealant stuff and it prolonged it for another 1.5 years. It's the stuff they sell at Walmart, small container about $20.