Plz HELP! When AC on, does your compressor make a whirring sound when you accelerate?

[Nut Kracker]

It can be very hard to determine where an A/C leak is coming from. That's why when checking for leaks, they put a dye in the system.
That allows the technician to see where the leak is coming from.
What year and model is you car? I thought it might have an automatic belt tensioner. Has it got only one belt, or one for each component?
If not the deflection should be around say.....6 to 10 mm. You should be safe with that.
The deflection is when you check the belt tension by pushing firmly on the belt with your thumb at a distance half way between the pulleys
and note how far the belt can be pushed (deflected). Measure this deflection with a ruler.

 

[Darren_L]

Interesting point!

All i know is that my alternator reads 13.65 (engine fans on high speed), 13.68 (engine fans on normal speed) when AC is on. 13.71 AC off! IDK if thats good or normal!

As for resistance and all what you said, i would appreciate it very much if you could tell me how exactly to check.

hook up a digital multimeter in line with the circuit
ie - grab your trusty multimeter, select DCV range. Disconnect your compressor connector. Connect one lead of the multimeter to the pin end of the connector and the other lead of the multimeter to the socket end. Start the car, turn the A/C on. If your system voltage is around 13.6v with the A/C on, then that's fairly much the voltage your meter should read when connected inline with the compressor wire. A voltage drop of maybe up to 0.5V would be acceptable, but no nmre more. If there is a significant drop, then you need to find where the resistance is in the circuit

 

[VK SL 3800]

Is your A/C guy putting sufficient oil in the system before he gases it?

 

[freefallin]

hook up a digital multimeter in line with the circuit
ie - grab your trusty multimeter, select DCV range. Disconnect your compressor connector. Connect one lead of the multimeter to the pin end of the connector and the other lead of the multimeter to the socket end. Start the car, turn the A/C on. If your system voltage is around 13.6v with the A/C on, then that's fairly much the voltage your meter should read when connected inline with the compressor wire. A voltage drop of maybe up to 0.5V would be acceptable, but no nmre more. If there is a significant drop, then you need to find where the resistance is in the circuit

So basically when i connect the multimeter it should read the same voltage as the alternator??
My alternator currently reads 13.71 when AC is off, so should it be reading 13.71-13.66 when i do this test?

 

[freefallin]

Is your A/C guy putting sufficient oil in the system before he gases it?

Yes VL! Ive seen him do it. About a half a shot glass worth...maybe a little more. Thats for the compressor.
As for the ac system, if it is to be oiled then i would think so cz its done by c machine.

 

[Darren_L]

So basically when i connect the multimeter it should read the same voltage as the alternator??
My alternator currently reads 13.71 when AC is off, so should it be reading 13.71-13.66 when i do this test?

with A/C on you said your alternator voltage (or battery voltage) is about 13.6v
so the compressor wire (with multimeter hooked up in series) shouldn't be less than say 13.1v. That's 0.5v drop which would be the maximum you would expect.

 

[freefallin]

with A/C on you said your alternator voltage (or battery voltage) is about 13.6v
so the compressor wire (with multimeter hooked up in series) shouldn't be less than say 13.1v. That's 0.5v drop which would be the maximum you would expect.

oh ok! Got it now! Thanks buddy! Will be doing that in a little bit!

 

[Trevor 062]

Mine does the same has done since I bought the vehicle, a bit annoying as it does sound like a supercharger as per the previous thread.
But it still works (touch wood), so I put up with it..

 

[freefallin]

hook up a digital multimeter in line with the circuit
ie - grab your trusty multimeter, select DCV range. Disconnect your compressor connector. Connect one lead of the multimeter to the pin end of the connector and the other lead of the multimeter to the socket end. Start the car, turn the A/C on. If your system voltage is around 13.6v with the A/C on, then that's fairly much the voltage your meter should read when connected inline with the compressor wire. A voltage drop of maybe up to 0.5V would be acceptable, but no nmre more. If there is a significant drop, then you need to find where the resistance is in the circuit

Hey Darren!
Ive done what you suggested above! Got weird readings, like not consistent and random. Got a question...is the AC clutch supposed to kick in when i connect the leads like what you suggested for the test?
If not, then why connect one lead to the connector wire and the other to the compressor socket? Why not just connect both leads to the connector wire and get the reading since that reading will be the voltage going to the compressor?

 

[greenacc]

My AC sounds like a friggin Mogwai ! ( from gremlins ! )
THere was a thread on here by a bloke with a VE who managed to figure out what was causing it and fix it. Apparently its common on VE's and it really shits me...........