So the air conditioning in my car hasn't been working since I bought it. I know for a fact that the compressor is okay, it's still turning. The coolant levels when I first tried getting it topped up said that the pressure was high, but the temp didn't change so the guy assumed the compressor was gone. Checked the compressor, all is fine and moving like normal. Went to a different place to have it topped up. They told me the coolant level was zero.... I assumed the ex-owners didn't use it or top it up so it had just ran out over years of neglect. So he tried to top it up with the a/c on.... but the system wouldn't accept any coolant....

Could the EVAP sensor cause the air con to act as if there was say a seized compressor or a blocked hose and just not accept new coolant? Or is it a case of compressor fine but hose blocked?

Think the first sounds more likely but I am wondering what else could cause this strange issue? My best assumption is that some sensor when I turn the car to cold, is assuming the car is at the "correct temperature" and therefore doesn't engage the a/c? The thing that is MOST confusing about it is simply there is SO little documentation (e.g. Youtube) about these clutchless compressors so whereas after watching many videos I know EXACTLY how a compressor works, I still have no idea how the a/c on a "always on" compressor actually works.... Anyway the reason I know the compressor is fine is because the rubber "safety thingy" (Love the word thingy, it can describe so much AND so little at once) hasn't sheared, and the centre bolt that holds the "clutch cover" (or so ive read it described on another forum) into the compressor (the black bit which has a spline centre that fits over the safety rubber and onto the compressors shaft) is also spinning when the belts rotating. If the compressor was seized then that rubber safety thingy wouldve sheared to stop the belt from being damaged on the pulley. 

So with that I will have a drum roll for your more experienced answers. Thanks

I'm the same, mine hasn't been working since I bought my car (4 years) lazy sod, been told by ATS that there is plenty of gas but the compressor isn't working so I've jumped the gun and Ive bought a second hand one off here and I'm taking it to a garage this Friday morning to investigate why it's not working.

One reason for the compressor not to work is if the wiring to it is broken.  It's reasonably easy to eyeball this wiring from under the car, and see if there are any obvious dangling wire ends. Might save a lot of (wasted) mechanical effort fitting another compressor, if there is a wiring fault.

 

As far as the OP's car goes, I can't make much sense of either garage's attempts to help you.  The first one seemed to think that pressure alone could tell you how much refrigerant was in the system, which isn't correct.  The second garage tried to top up the system while the A/C operating? Really? That doesn't sound right to me, though I'm no expert.

AFAIK nothing that any of the sensors might be reporting or failing to report, could affect whether refrigerant could be introduced into the system.  The machine that is trying to service the AC might not allow top-ups if it detects a leak though. This might be what's happened at your second garage, but they haven't described the situation to you very well?

No they were just using the old bog standard pressure hose with the pressure gauge attached to a bottle of coolant, both times. I just bought a vag com scanner to test my car, and 2 interesting fault codes popped up though! 
 

Address 08: Auto HVAC        Labels: 6Q0-820-045.lbl

   Part No: 6Y0 820 045 

   Component: Klimaanlage        X0770  

   VCID: F2ED2C93BE2D738E1D9-50E6

 

2 Faults Found:

00818 - Sensor for Evaporator Outlet Temperature (G263) 

            30-00 - Open or Short to Plus

00819 - High Pressure Sensor (G65) 

            07-00 - Signal too Low

 

Both could cause lack of air con.... but both may not be the cause of my problems either... 

Second of those is consistent with there being insufficient refrigerant. First one needs fixing.

So that sensor is that the evap sensor that is a common fault with skoda's? I've read about a fair few people changing them because of a/c issues? 

Common enough for some kind person to have prepared a guide for replacing it.

 

My only tip - having done this job - is to pay a lot of attention to exactly where it comes out of and the angle it goes in/out of there as you're removing the old one. The hole it goes into takes a bit of finding by feel if you don't have a good mental picture of it.  You can't really get your head anywhere near to get a line of sight on it.

 

I would suggest you first take the car to somewhere who seem to know what they're doing w.r.t. AC first though, in case there is a serious, expensive-to-fix leak which might make you change your mind about needing AC.

Finding out if there is a leak should be pretty simple, as the ac has had a bit of gas put in it, and I know this, then if I take it to get checked (for free I might add haha) and the pressure is zero again then a leak is pretty likely and will save me spending £60 to have it checked for leaks. I could buy the equipment and check for leaks myself but I have 2 children and I am currently off work due to illness and awaiting surgery so even though I am on benefits we have so little money going spare so I save/fix what I can myself before taking the car to a professional. I have only taken my car to a garage a few times, and every time they say they know what the problem was, then it turnt out it wasnt that, and that is ALOT of money I couldve avoiding spending. In the end we had to do the work ourselves anyway! 

Ever since I bought the car there has been a vibration at speed. Not deformed tyres (aforementioned trip to garage) not tracking, which they said they couldn't do because track rods were seized and the tracking was "barely" out, even though me and my step dad managed to unseize them when we changed the wishbone+hub bearing+suspension due to the bearing failing mot and bearing being seized, along with lower ball joint, cv joints are good, but the car had a dent on the front left wing and some damage to the steel wheel cover on the left side wheel... so my only last guess is that its either a wonky driveshaft, or the inner cv joint is gone.... I ONLY bought a fabia because its my second year driving and the insurance for the fabia is astonishingly cheaper than any other car I quoted. 

Sorry for the life story haha Been a long day!!

Common enough for some kind person to have prepared a guide for replacing it.

 

My only tip - having done this job - is to pay a lot of attention to exactly where it comes out of and the angle it goes in/out of there as you're removing the old one. The hole it goes into takes a bit of finding by feel if you don't have a good mental picture of it.  You can't really get your head anywhere near to get a line of sight on it.

 

I would suggest you first take the car to somewhere who seem to know what they're doing w.r.t. AC first though, in case there is a serious, expensive-to-fix leak which might make you change your mind about needing AC.

I've had a similar problem with yours, it turned to be caused by nothing than mud stuck on the inner side of the wheels and they only needed a good wash. At that time, I've also had all four wheels balanced to make sure everything was alright. The steering wheel is now rock solid even at 100mph. 

I've had a similar problem with yours, it turned to be caused by nothing than mud stuck on the inner side of the wheels and they only needed a good wash. At that time, I've also had all four wheels balanced to make sure everything was alright. The steering wheel is now rock solid even at 100mph. 

 

EVERYTHING in this car is mucky so you could be perfectly rightt!! I have a wire wheel, so if I get some paint when I can afford to, I'll clean off the wheels and take them to be balanced. I mean the corrosion on this car and all the seized parts doesn't appear to be JUST rust, it looks like its been frequently caked in mud and not cleaned off so it has a THICK layer of rust/mud/corrosion that is really strong! Honestly of all the corrosion, almost none is actually rust colored, all a pale light brown. To be honest, after the car being at the garage to try and fix this problem and their answer being "deformed wheels" I also found out they had let down the pressure to 21psi.... Now I usually carry a pram, a heavy toolbox, our daughter me and my partner, so I "generally" as a rule keep the tyres near-ish their "full load" pressure. Once I Put the back tyres up to 40 psi and the front 2 to 31 psi, the vibration reduced SIGNIFICANTLY, its still there but nowhere near as strong. 

Back to the a/c thing, does ANYONE have any info on how the clutchless a/c system is meant to work and any ideas as to why with a working compressor, the system doesn't accept much gas? Probably the evap sensor im sure, but its a pain I dont want to go through just to find out the a/c system has a blockage or something stupid that requires a total overhaul we can't afford!! Luckily its nearly winter, our newborn is due next week and hopefully (HOPEFULLY) by next June/July I will have had my op AND saved up enough money to buy a car that DOESNT have every single "typical" problem of that particular model lol