A/C problems

My air conditioner has gone flakey on me but the symptoms aren't
consistent so I haven't been able to get a diagnosis. It blows hot
and cold.

Usually, when I first turn it on, it blows cold.... for awhile, maybe
10-15 minutes (or more or less).... then the cold goes away and it
feels lmore ike outside air blown by the vent fan.
But if I leave the control on "A/C, it might start blowing cold air
again after another 10-15 minutes. When I'm driving, I can't hear
anything turning on/off under the hood nor can I feel anything.

Jiffy Lube guy (who also services A/C) couldn't make it act up when he
checked it and he guessed it might be hoses freezing up. The
dealership couldn't make it act up either and they guessed it would be
the compressor clutch, so best to replace the whole compressor (for
about $1000). Both Jiffy and dealer told me to bring it back in when
it's not working. But my crystal ball stopped working years ago and I
never KNOW when it's going to work and when it's not. It both comes
and goes with no warning and no regularity.

Anybody want to take a stab at what the problem might be? And better
yet, an inexpensive way to nurse it along through the summer?

Rick
HeBeJeepN
'99 XJ Sport, Selec-Trac, Trac-Lok

On 7/1/2011 11:13 AM, lid wrote:
> My air conditioner has gone flakey on me but the symptoms aren't
> consistent so I haven't been able to get a diagnosis. It blows hot
> and cold.
>
> Usually, when I first turn it on, it blows cold.... for awhile, maybe
> 10-15 minutes (or more or less).... then the cold goes away and it
> feels lmore ike outside air blown by the vent fan.
> But if I leave the control on "A/C, it might start blowing cold air
> again after another 10-15 minutes. When I'm driving, I can't hear
> anything turning on/off under the hood nor can I feel anything.
>
> Jiffy Lube guy (who also services A/C) couldn't make it act up when he
> checked it and he guessed it might be hoses freezing up. The
> dealership couldn't make it act up either and they guessed it would be
> the compressor clutch, so best to replace the whole compressor (for
> about $1000). Both Jiffy and dealer told me to bring it back in when
> it's not working. But my crystal ball stopped working years ago and I
> never KNOW when it's going to work and when it's not. It both comes
> and goes with no warning and no regularity.
>
> Anybody want to take a stab at what the problem might be? And better
> yet, an inexpensive way to nurse it along through the summer?
>
> Rick
> HeBeJeepN
> '99 XJ Sport, Selec-Trac, Trac-Lok

First, stop going to JiffyLube... They have ruined more good vehicles
than anything else. They can't change oil properly, so no way they can
do A/C service right either.

I'm guessing here, but consider a fault in the blend door allowing
heated air to mix in improperly.

I don't think it is the compressor...

I'd suggest a competent A/C shop. Yea, I know those are hard to find!

--
I'm never going to grow up.

HeBeJeepN wrote:
>> My air conditioner has gone flakey on me but the symptoms aren't
>> consistent so I haven't been able to get a diagnosis. It blows hot
>> and cold.
>>
>> Usually, when I first turn it on, it blows cold.... for awhile, maybe
>> 10-15 minutes (or more or less).... then the cold goes away and it
>> feels lmore ike outside air blown by the vent fan.
>> But if I leave the control on "A/C, it might start blowing cold air
>> again after another 10-15 minutes. When I'm driving, I can't hear
>> anything turning on/off under the hood nor can I feel anything.
>>
>> Jiffy Lube guy (who also services A/C) couldn't make it act up when he
>> checked it and he guessed it might be hoses freezing up. The
>> dealership couldn't make it act up either and they guessed it would be
>> the compressor clutch, so best to replace the whole compressor (for
>> about $1000). Both Jiffy and dealer told me to bring it back in when
>> it's not working. But my crystal ball stopped working years ago and I
>> never KNOW when it's going to work and when it's not. It both comes
>> and goes with no warning and no regularity.
>>
>> Anybody want to take a stab at what the problem might be? And better
>> yet, an inexpensive way to nurse it along through the summer?
>

On Fri, 01 Jul 2011 11:44:08 -0600, Will Honea wrote:
>From the sympthoms, I would first guess low refrigerant charge. Per
>PeterD's suggestion, find a competent a/c shop and have them check it. Low
>refrigerant will cause freeze-up in several places, mainly in the expansion
>valve, but you need someone who has the right equipment and knowlege to get
>the charge right, especially with R134a - too much is as bad or worse than
>not enough and it's not real easy to figure it out unless you start with an
>empty, pumped down system.
>
>Beware of one money pit: regulations require that the shop fixes the leak
>before re-charging. If you get a serious attack on your wallet about
>"finding the leak", you need to find another shop. A good shop will sniff
>the system then bring the charge up to spec to retest unless it's pretty
>much empty. That's not too expensive but a lot of places see any potential
>"leak" as a money tree!

Yep, that was my first guess too and that was the first thing both
shops hooked up and checked. I'll go with PeterD's skepticism of
Jiffy Lube but the dealership guy has a reputation for being top notch
plus factory trained with diplomas and certificates plastered all over
the waiting room walls. So I'm guessing his gauges didn't lie to him.
And he's the one that guessed it could be the compressor clutch going
bad. I didn't get a chance to talk to him directly though or I would
have asked him about other possibilities.

I have one more shop I'm going to try. It's an independent Jeep guy
but not an AC specialist. You'd think there would be a specialist here
of all places, I'm in the deep south. But two of the best ones nearby
blew away in Katrina and didn't come back. I'm thinking though that
any of these shops will be able to figure it out if I can just get it
to do its flaky act while it's right there in front of them.

Thanks for the response though.

Rick

"Will Honea" > wrote in message
...
> lid wrote:
>
>> My air conditioner has gone flakey on me but the symptoms
>> aren't
>> consistent so I haven't been able to get a diagnosis.

> Beware of one money pit: regulations require that the shop
> fixes the leak
> before re-charging.


Depends on the state.

EPA does not require this.

Apple2Steward wrote:
> "Will Honea" > wrote in message
> ...
>> lid wrote:
>>
>>> My air conditioner has gone flakey on me but the symptoms
>>> aren't
>>> consistent so I haven't been able to get a diagnosis.
>
>> Beware of one money pit: regulations require that the shop
>> fixes the leak
>> before re-charging.
>
>
> Depends on the state.

Make them quote the reguation.

> EPA does not require this.

Yep.

Still though, a well maintained system should _never_ go down.
Most common clulprit is the bayonette connection at the AC
compressor due to vibration. Just remember to never
overtorque the bolts. Dead giveaway is dirt accumulation.
That's due to dust sticking to the oil that gets out with the
refrigerant.

For ref, I have only had to add R134 to my 1993 ZJ once. And
that was due to engine vibration loosening the connection to the
compressor back in 2003 or so. Replaced the O rings and put
a bit more in to blow out any atmosphere, then filled it up.
A little over 104 today and the AC was working like a champ.
--
DougW

Typical failing clutch symptoms. Easy to check, too. When it stops
working, pull over, leave it running with the A/C on, open the hood
and look at the compressor clutch. If it's engaged, that's not your
problem. If it's not, grab your favorite tool (hammer) and tap the
compressor near the clutch. If it engages, you need a clutch. Pretty
common occurrence on an XJ. Clutch can be changed separately, too.

Jiffy Lube? Wouldn't even let them change my oil...



On Fri, 01 Jul 2011 10:13:30 -0500, lid wrote:

>My air conditioner has gone flakey on me but the symptoms aren't
>consistent so I haven't been able to get a diagnosis. It blows hot
>and cold.
>
>Usually, when I first turn it on, it blows cold.... for awhile, maybe
>10-15 minutes (or more or less).... then the cold goes away and it
>feels lmore ike outside air blown by the vent fan.
>But if I leave the control on "A/C, it might start blowing cold air
>again after another 10-15 minutes. When I'm driving, I can't hear
>anything turning on/off under the hood nor can I feel anything.
>
>Jiffy Lube guy (who also services A/C) couldn't make it act up when he
>checked it and he guessed it might be hoses freezing up. The
>dealership couldn't make it act up either and they guessed it would be
>the compressor clutch, so best to replace the whole compressor (for
>about $1000). Both Jiffy and dealer told me to bring it back in when
>it's not working. But my crystal ball stopped working years ago and I
>never KNOW when it's going to work and when it's not. It both comes
>and goes with no warning and no regularity.
>
>Anybody want to take a stab at what the problem might be? And better
>yet, an inexpensive way to nurse it along through the summer?
>
>Rick
>HeBeJeepN
>'99 XJ Sport, Selec-Trac, Trac-Lok

lid wrote:
> My air conditioner has gone flakey on me but the symptoms aren't
> consistent so I haven't been able to get a diagnosis. It blows hot
> and cold.
>
> Usually, when I first turn it on, it blows cold.... for awhile, maybe
> 10-15 minutes (or more or less).... then the cold goes away and it
> feels lmore ike outside air blown by the vent fan.
> But if I leave the control on "A/C, it might start blowing cold air
> again after another 10-15 minutes. When I'm driving, I can't hear
> anything turning on/off under the hood nor can I feel anything.
>
> Jiffy Lube guy (who also services A/C) couldn't make it act up when he
> checked it and he guessed it might be hoses freezing up. The
> dealership couldn't make it act up either and they guessed it would be
> the compressor clutch, so best to replace the whole compressor (for
> about $1000). Both Jiffy and dealer told me to bring it back in when
> it's not working. But my crystal ball stopped working years ago and I
> never KNOW when it's going to work and when it's not. It both comes
> and goes with no warning and no regularity.
>
> Anybody want to take a stab at what the problem might be? And better
> yet, an inexpensive way to nurse it along through the summer?
>
> Rick
> HeBeJeepN
> '99 XJ Sport, Selec-Trac, Trac-Lok

I'm wondering myself. My car does this exact thing. Blows nice and cold
for 15 to 20 minutes, then the compressor won't click. The car will turn
on the fans and speed up the engine, but no click and no compression.
I can't get AC again unless I stop the car for a few hours, then 15 to
20 minutes again. Before it won't click anymore, the compressor is slow
to engage. I've heard everything from TXD to water in the lines to bad
clutch. It's a clunker car so I don't want to spend a fortune, I just
want some AC for our sponge bath air here in Baltimore!

Right now it's 80 degrees out but it just rained so we're close to the dew point,
and no breeze. You start to sweat in about 2 minutes out there...

On 7/4/2011 11:14 PM, Scott in Baltimore wrote:
> lid wrote:
>> My air conditioner has gone flakey on me but the symptoms aren't
>> consistent so I haven't been able to get a diagnosis. It blows hot
>> and cold.
>>
>> Usually, when I first turn it on, it blows cold.... for awhile, maybe
>> 10-15 minutes (or more or less).... then the cold goes away and it
>> feels lmore ike outside air blown by the vent fan.
>> But if I leave the control on "A/C, it might start blowing cold air
>> again after another 10-15 minutes. When I'm driving, I can't hear
>> anything turning on/off under the hood nor can I feel anything.
>>
>> Jiffy Lube guy (who also services A/C) couldn't make it act up when he
>> checked it and he guessed it might be hoses freezing up. The
>> dealership couldn't make it act up either and they guessed it would be
>> the compressor clutch, so best to replace the whole compressor (for
>> about $1000). Both Jiffy and dealer told me to bring it back in when
>> it's not working. But my crystal ball stopped working years ago and I
>> never KNOW when it's going to work and when it's not. It both comes
>> and goes with no warning and no regularity.
>>
>> Anybody want to take a stab at what the problem might be? And better
>> yet, an inexpensive way to nurse it along through the summer?
>>
>> Rick
>> HeBeJeepN
>> '99 XJ Sport, Selec-Trac, Trac-Lok
>
> I'm wondering myself. My car does this exact thing. Blows nice and cold
> for 15 to 20 minutes, then the compressor won't click. The car will turn
> on the fans and speed up the engine, but no click and no compression.

A marginal refrigerant level (low, but just above the low pressure
cutoff) will cause this to happen. The system, when cold has less
pressure overall, and the low pressure switch then cuts off. After the
system warms up (say it sits for a while) it then starts up again.

>

--
I'm never going to grow up.

>> I'm wondering myself. My car does this exact thing. Blows nice and cold
>> for 15 to 20 minutes, then the compressor won't click. The car will turn
>> on the fans and speed up the engine, but no click and no compression.
>
> A marginal refrigerant level (low, but just above the low pressure
> cutoff) will cause this to happen. The system, when cold has less
> pressure overall, and the low pressure switch then cuts off. After the
> system warms up (say it sits for a while) it then starts up again.


It's not low. It's a 23 oz system and I just put a can and a half in it.
It has a real slow leak so I have to fill it every summer.

On 7/5/2011 7:56 AM, Scott in Baltimore wrote:
>>> I'm wondering myself. My car does this exact thing. Blows nice and cold
>>> for 15 to 20 minutes, then the compressor won't click. The car will turn
>>> on the fans and speed up the engine, but no click and no compression.
>>
>> A marginal refrigerant level (low, but just above the low pressure
>> cutoff) will cause this to happen. The system, when cold has less
>> pressure overall, and the low pressure switch then cuts off. After the
>> system warms up (say it sits for a while) it then starts up again.
>
>
> It's not low. It's a 23 oz system and I just put a can and a half in it.
> It has a real slow leak so I have to fill it every summer.

What do the running pressure gauges show, both high and low side?

--
I'm never going to grow up.