My Mother just came up to NH with her '03 GT Limited sedan. She complained that teh A/C did not wor the whole way. So I checked and when the A/C button was pressed the clutch on the compressor engaged but the low pressure line was not geting cold? I thought if system was too low on freon it would not even engage the compresor??

 

I got some R134A and recharged the system working great now, but would not have exspected a '03 with only 77k to leak in teh A/C yet??

Its pretty common for these systems to leak a little around the line fittings where the o-rings are...sometimes you can take some soapy water and spray a little there and you will get a little bit of bubbling...Personally Im not one for the little can with the low psi. side gauge....How do you monitor the high side when using one of these?...you cant...unless or course you have a set of manifold AC gauges...

O rings leak, they aint exaclty the highest tolerance part there is in a car.

 

Can happen to any car any age, and sometimes right in the lot before its sold.

 

 

nipper

Yeah, I just worked on an 08 Impreza today that was undercharged, couldn't find any signs of leaking, even went around with the freon sniffer...

 

I worked on a Tundra once that never had the refrigerant put in at the factory! Had a vacuum in the system when I hooked the machine up.

I worked on a Tundra once that never had the refrigerant put in at the factory! Had a vacuum in the system when I hooked the machine up.

craziness.

 

the orings are easy to replace....you just loose your charge. i've filled them up after replacing orings numerous times with 100% sucess rate so far. it's only one bolt to replace each oring, so the system is only open for a very short time, i can't imagine much air is actually getting in there. no more than the system can easily dissipate.

 

i know it's not ideal, but it works.

With my 93 legacy wagon after about 12 years from new started leaking r12. My dad is in HVAC and just recharged it, but usually needed to be refilled after winter. Did that for a few years. Then it leaked a bit more worse and needed to be topped off every month, then he ran out of r12... so my dad vacuumed the system, and got those r134a bottles which are compatible with r12 systems, and there stop leak product. So far been over a year and the car has been sitting for a few months now even through winter and went outside today started it up, A/C worked no problems, and the line was ice cold instantly!

 

My 94 Legacy has r134 and is still working no problems. Not sure if the previous owner serviced it though.

 

BTW with the 93 tried to find leaks, but my dads $400 or something leak detector found nothing even on the highest setting. Seemed to be a issue mainly when it was cold.

 

Anyother thing, cycling the A/C every so often probably helps the A/C hold a charge as welll considering it helps keep everything lubed up.

Well a week latter the system was low again and no cold air. My Mom had Metric Motors in NY recharge the system with dye for $164 and look for leaks. Hope they can fix it.

$164???? Good LORD! Maybe its just the price diff east to west, but that's just highway robbery to me!

 

Having said that, I'd say they are at least on the right track. Charge it, throw some dye in it, come back in a week or so. Or whenever it stops blowing cold. As has been said, the most common point of failure is the myriad of o-rings in the system.

 

Depending on which style of compressor you have, there will be at least 1 and perhaps up to 4 on the fittings at the compressor. There will be at least 1 each for the inlet and outlet on the condenser coil. There will be at least 3 on the receiver/dryer. 2-4 at the expansion valve and 2 more at the evaporator coil. IF they are going to set about replacing o-rings, whether they replace 1 or all, make SURE that they also replace the reciever/dryer. Its usually about a $30-40 part, but its worth far more than that as insurance for your A/C system. R134a is corrosive in the presence of moisture. Since most of your A/C system is constructed of fairly thin aluminum, this will eventually result in having a convertible A/C system. Well, ok....a converted A/C system. So its important to keep that reciever/dryer in good shape. If they are going to have the system open for any reason, its probably a good idea to change it.

[...]Personally Im not one for the little can with the low psi. side gauge....How do you monitor the high side when using one of these?...you cant...unless or course you have a set of manifold AC gauges...

Those cans with a built-in gauge won't replace a manifold gauge set, but they're not as useless as it might seem. If you know the refrigerant being used, and the ambient temperature, it's possible to determine the approximate level of charge by reading a single gauge when the engine is off (that is, compresssor not running and time allowed for the system to equalize). If that's in the ballpark, and with the system running the low side pressure is also about right, it's likely the system is close to correct charge and operation. Having a high side gauge is nice, but not always absolutely necessary.