AC stopped working for the first time in the life of the vehicle (2005 Odyssey). I verified the relay is okay. I assume the refrigerant just finally got low enough to trip the low pressure switch. I scheduled a visit with my local guy but won't be until next Thursday so I figured I could try a $30 kit with some stopleak in it just to see if it's simply too low to kick on. I don't know if it would be worth adding a drop or two of UV die or PAG oil (I think they make this a combo nowadays). Any advice would be appreciated, especially if I missed a basic troubleshooting step.
Going to try an AC recharge kit, should I add oil or UV dye?
- Thread starter jayjr1105
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Get the cheapest cans of 134 you can, and purchase the tools to add it. Since the system is old, you will likely need to do it again.
I'd wait for the mechanic before messing with it. A kit with stop leak is asking for trouble imo.
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get a plain old can of R134a and a hose and add it to the system. Don't ever put stop leak in a A/C system.
You can add dye if you want to help your A/C guy determine why the system was low but at this point in time you're not really sure why it's not working so that step is entirely up to you.
Again... no stop leak.
You can add dye if you want to help your A/C guy determine why the system was low but at this point in time you're not really sure why it's not working so that step is entirely up to you.
Again... no stop leak.
I did this once on a 1983 Buick Regal wagon. AC died on a hot July day.
A single parts store can with adapter included worked perfectly.
An AC guy told me there are "threshold amounts" of gas needed. The one can got us past that threshold.
I believe there was dye in the canned product...no mention of additional PAG oil, as I recall.
'Twas a long time ago.
The AC continued to operate for another two years.
Then the engine blew. Dad knew about engine oil but little about checking its level.
This was the car which drained a pint of oil during a Thanksgiving oil change.
The Buick became a '91 Taurus 'Program car' (Budget Rental fleet return). <<A great "small town America" car story.
A single parts store can with adapter included worked perfectly.
An AC guy told me there are "threshold amounts" of gas needed. The one can got us past that threshold.
I believe there was dye in the canned product...no mention of additional PAG oil, as I recall.
'Twas a long time ago.
The AC continued to operate for another two years.
Then the engine blew. Dad knew about engine oil but little about checking its level.
This was the car which drained a pint of oil during a Thanksgiving oil change.
The Buick became a '91 Taurus 'Program car' (Budget Rental fleet return). <<A great "small town America" car story.
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- 83
I would avoid the "R134A replacement" cans if possible. They do NOT contain any R134A! I don't know how this is even legal.
I would attach a gauge and check the line pressures first.
If his AC machine identified stop leak it will shut down and won't allow him to work on the car.
Just because an ac system isn't cooling does not mean that it's got a leak. Many other things can go bad.
Just because an ac system isn't cooling does not mean that it's got a leak. Many other things can go bad.
You don't mention if the non-operation was sudden. Was it working fine one day and suddenly stopped? That's different than deteriorating system performance over several days with shorter and shorter clutch cycling (which might be indicative of a slow leak).
The most basic troubleshooting step is to visually assess every joint for weepage/leakage. Leaky joints have a propensity to accumulate a little sooty buildup at the leak point(s). Also closely inspect the front of the condenser for physical damage (such as rock/road debris damage).
After that, you can manually jump the compressor using a 12V source to ensure the clutch actually engages.
Then you'd need a set of manifold gauges to check system pressures.
A/C systems are carefully balanced sealed systems which require actual diagnosis. Merely adding some refrigerant from a kit found on an endcap at Auto Zone is not diagnosis.
BTW, even in the event of a slow leak, you needn't add oil. The oil tends to settle throughout the system and is generally replenished only when a system component is replaced.
If you don't want to pony up for the proper gauges ($64.99 at Harbor Freight), this is best left to a professional.
I'm gonna be different in this case and say , you have a 20 year old car with a leaky air conditioner, try the freon with stop leak in it. What do you have to lose?. My Equinox had a leak for the last few years, and a can of freon with stop leak slowed it down alot. I put it in a year ago, and it was still making cool air as of June. I bought a can of 134a at the local auto-parts store for $11.99, and topped it off. If that lasts another year, or if I have to add another can before that, it will be alot cheaper than taking it to a shop and hope they can fix it for under $1,000. Nobody here has said don't use stop leak, but no reasons are given. I guess they say that, because that's what it says on the internet.,,
As mentioned above, if the system has stop leak in it, repair shop evacuation/recharge equipment will detect the foreign material (stop leak) and shut down.
If the car in question is on the path towards the scrapyard in a couple of years, I'd day go ahead with the stop leak and dumping in a can of refrigerant. If the car has a longer glide path, you may be shooting yourself in the foot using it.
Because stop-leak products (including those for cooling systems, PS systems, etc.) are designed to react to air and moisture and can adversely affect the system if they harden in the wrong place, causing potential seal and/or component damage.
These products are not a proper substitute for actual diagnosis and repair...and can cause unintended problems.
Now if the OP's Odyssey is a beater and he doesn't care if the system is damaged, then sure, give it a try. If he cares about the system's long-term viability then he should do it right.
How sure are you that the stop leak part actually worked? I'm thinking that part was more of a placebo effect.
A/C stop leak plugged the oil passage in the accumulator on my Volvo, destroying the compressor and nearly taking out the engine's valvetrain when the A/C drive belt broke and jammed up into the timing belt!
It would be helpful if you had absolute proof that stop leak caused your problem, instead of just assuming it did.,,
It may not have stopped the leak entirely, but it seems to have slowed it down to the point 1 can costing $11.99, kept me cool for 9 months. I'd say that was the best way to deal with it. I won't be keeping my car for more than 2 or 3 more years, and I'll keep doing that until it's gone.,,
