Car AC Diagnosis of Various Symptoms Dedicated Thread

[hasnat7]

Aoa I have Alto vxr 1000 as my second car. It was working perfect in all respect but this summer when I switched on th AC it worked perfect. After a few days I switched it on but the compressor doesn't start. Due to lockdown I cannot leave the area to approach any mechanic. Can anyone guide me. I checked gas and it is there. Thanks

[sadatmasood11]

AssSalamOAlikum
@ Muhammad Akmal
Sir Ap ki car ki gas puri hai toe compressor ka time Pura ho Gaya hai.
Brv compressor is not too good.
Replace the compressor with kabli one cost you around 11000 for perfect and more better cooling than previous one.
We already replaced 2 compressors of brv and customers are very much satisfied.

Cartech autos
Syed Sadat Masood
03224450322
320-D Johar town
Lahore

[Massive_One]

Cartech autos Syed Sadat Masood 03224450322 320-D Johar town Lahore

Sadat bhai,
I have Swift second hand, owner was using water in it, not coolant.
I want to change it to coolant.
but the problem is... after driving in city, car's coolant reservoir bottle is empty, but water is full in radiator (when i check water level after the car cools down).
what could be the problem ?

[akmal199511]

Problem diagnosed AC gas is overfilled

Solution: Mechanic completely remove the gas and vacuum it and then fill again (Amrican branded) gas.

[akmal199511]

Now I want to know Is this time gas is properly filled.
Lower Side 40
Higher Side 230~250
Car: Honda BRV

Car Mannual says = 555~605 Gram gas can be added in system

[xzap042]

Since it was vacuumed and filled again, didn't you charge by weight?

[akmal199511]

No sir
Is it necessary to charge by weight?

[Xulfiqar]

It is the only way to charge a system

Because pressure is affected by temperature, meaning even if you have correct gas charge but a clogged fin condenser or bad fan you can see 350 psi head pressure at idle

Never let mechanic charge by pressure, always charge by weight

[akmal199511]

Thanks sir for guidance

[pwuser159302919527]

I have a cultus vxli 2009. Today i bought a set of manifold for inspection of gas pressure in my car AC and Home Split Ac's.

When Car AC system not running and ambient at around 32 C (as per Google)

Low side and High side Pressure were 110 Psi.

After running Car AC following were the results:

Low side Pressure: ~56-59 Psi
Low Side Temperature: ~74 F (23.3 C)

High Side Pressure: ~250 Psi
High side temperature not noted

My issue is that the car cools fine in evening but does not cool a little in peak daytime.

[Massive_One]

does not cool a little in peak daytime.

if it is parked under the sun, then do not expect it to do any cooling soon unless you continuously drive it for a good 10-15 minutes.

[pwuser159302919527]

If it's parked under the sun, then there is no cooling at all. I mean, I literally sweat inside the car. Even continuously driving for 30 to 40 mins.

Today when I came back home, it was 36 C Temperature (As per Google), so I checked the pressures again and to my surprise, the pressures were up from what I measured at 32 C Temperature yesterday:

Low Side: 75~80 Psi
High Side: around 300 or above. (Sorry I do not remember the exact figure)
Air Temperature blowing of Ac duct: 26~27 C

[Xulfiqar]

did you check the running system pressure after 15 minutes?

if yes - its a bit overcharged or the gas is adulterated with air.

[Xulfiqar]

is your condenser fan actually working? - do a full refresh, meaning remove this gas, pull a solid vacuum and recharge by weight only.

[pwuser159302919527]

Yes, I checked the pressure after 10 to 15 minutes and Yes condenser fan is running. I can only tell you that. It's working properly or not, I don't know. Maybe if you guide I'll try to perform the test.

Also, I don't exactly know how much weight of gas should I charge in this system as there is no sticker under the hood. If anyone knows the amount for stock AC of cultus VXLI 2009 it would be very helpful.

In case, if I don't know the amount, what will be the procedure then??

I do have a vacuum pump single stage 3cfm. Is this enough for Car and Home AC's??

Also to add one thing I am confused about, as soon as start the car and turn on AC, I get cold air but after a few minutes, the cooling efficiency decreases, and I only feel cool air when I put my hand near the Supply Air Wings.

[abdkhan2]

Low side is very high maybe its overcharged or compressor is very weak

[Xulfiqar]

compressor is good - he is getting over 300 psi head pressure when hot.

All signs lead to an overcharged system here.

[abdkhan2]

Then why pressure switch not reponding.?

[Xulfiqar]

it will kick in at 350 and above, or has been disabled (usual case in Pakistan)

[xzap042]

Also, I don't exactly know how much weight of gas should I charge in this system as there is no sticker under the hood. If anyone knows the amount for stock AC of cultus VXLI 2009 it would be very helpful.

It's written on evaporator box under dash. In case of Carby Cultus I believe it's 450g of R410a