Mazda AC trouble, help please.

[XdzelatX]

Hi all, and thanks for your time.

I drive:
2001
Mazda
323f
2.0 DiTd 101hp

So i have trouble with AC not being able to cool down properly.I can only measure on low side of Ac line, and my pressures is like this:

Gas is R134a, outside temp is around 25 Celsius
Low side static pressure AC off 75 psi (AC was off for 24h at this moment)
Idle AC on (~850 rpm) 15 psi
Drops to 0 psi at 2000 rpm
At 2500 rpm clutch kicks off and pressure goes up to 55-60 psi
And kicks in again when rpm is idle pressure is then at 15 psi.

So do i need to only add more R134a in it, or there might be some other problem?

[tbirdtbird]

You most likely have a leak. It needs to be found, fixed, and the correct charge weighed in, most likely at an AC shop.
Randomly adding in a can of 134 will not work properly and will likely leak out in short order.

Has the system ever been serviced before?
Has anyone added any leak sealer?
Is this a USA car?

[JohnHere]

Welcome to our Forum.

Has the system ever been serviced? If not, it could be just low on refrigerant due to slight losses over the past 20-odd years. But it could also have a larger leak.

The first thing I recommend is to evacuate and recharge it to specs, then evaluate cooling performance and re-check pressures. Also leak-test the system.

However, the ambient temperature of 25C (77F) is a bit low for testing purposes. I would wait until the daily temperatures are at least 27C (80F).

[DetroitAC]

You have a completely normal low charge for the age of your Mazda. Take it to a good AC shop to be recharged.

[XdzelatX]

Thank u all for replies
No, it's EU car.
About servicing and leak sealer i don't know, i drive it around 10 months now, and i don't have history of AC servicing (but i guess not, philosophy here is check it only if it falls off -.-) And last week i hit round 350000 Km and only problem is AC XD

And here comes my biggest problem. I don't have AC shop near me, and i cant get to them because of work, when i am free they are closed ect...
Is it safe if i only add refrigerant for now till i work something for proper servicing, or does it need to be evacuated and recharged anyway?

[JohnHere]

The problem with "topping-off" refrigerant, which is widely discouraged, is that you don't know how much is in the system now, and you don't know how much to add. And the pressures won't tell you, either. So essentially, topping-off is mere guessing, which could damage the system. The best and preferred method is to charge into a well-held vacuum and to weigh-in the precise amount of refrigerant using an RRR machine that professional shops normally have, or by using a refrigerant scale.

[tbirdtbird]

"And here comes my biggest problem.... etc"
I knew you would say this.
I personally think you have less than 1/2 the 134 charge going from the pressures you posted.
We cannot stop you from adding one can of 134.
BUT please do not be alarmed if it doesn't work.
Evacuation and filling by weight is by far the best way to approach this, as 3 of us have already stated.

Potential problems with adding a can yourself:
1. Accidentally buying a can of refrigerant that has sealer in it. DO NOT use any sealer, you will make your problems 10X worse
2. Accidentally getting air into the system (then it won't work well at all)
3. Only having the low side gauge puts you at a huge disadvantage
4. I still suspect a leak, and putting in more 134 without leak detection equipment will be a wasted effort

[XdzelatX]

Thanks again
I will manage somehow until i have time to go to AC shop.

[JohnHere]

I will manage somehow until i have time to go to AC shop.

Unless you have the proper equipment and know-how, I think taking it to a professional A/C shop is your best bet.