MK5 Golf GTI

All Things Mk5 => How to Guides / Troubleshooting => Topic started by: Atreah on May 03, 2017, 07:20:59 pm

Title: Aircon not blowing cold air
Post by: Atreah on May 03, 2017, 07:20:59 pm
Hey everyone,

so, I've had this issue for a while now and have decided to get around to fixing it. When I bought the car, the AC seemed to work fine (not the best AC I've ever seen, but it did the job). Anyhow, at some point, the air-con stopped blowing cold air. It just never gets really cold at all. Apparently, there's still gas in the system and there aren't any pressure leaks, so I'm thinking something must've died. I am aware of the dreaded compressor blow-outs and metal shavings in the system, but I never heard the AC make any weird noises and it still makes exactly the same sound as it always has (however, I don't run it now).

I am just wondering if this could still indicate a compressor issue? Or would there be any other signs if the compressor had "exploded" into the system, apart from not having any cold air?

I'll be taking the car to an AC mechanic soon-ish, but I'd like to hear more opinions before I do so.

Thanks!
Title: Re: Aircon not blowing cold air
Post by: MIJ_JAGGER on May 03, 2017, 07:33:01 pm
Is your ambient temp reading ok?

The A/C compressor won't run if the car is reading ambient temp below 5 degrees
Title: Re: Aircon not blowing cold air
Post by: Atreah on May 03, 2017, 09:01:54 pm
Huh, I had no idea! Guess what - the ambient temp sensor died some time ago, so it reads "----". Thanks a lot for this! I'm not sure if the air-con stopped blowing cold air before the sensor died or not though, but it could definitely be the cause and I would probably wreck my head trying to figure out what's wrong with the AC if that is the case. I'll order one asap and hopefully it fixes my issue; when I get the temp sensor, I'll report back!

Again, thanks a bunch! You might've saved me a whole lot of hassle.
Title: Re: Aircon not blowing cold air
Post by: MIJ_JAGGER on May 04, 2017, 12:59:33 am
Title: Re: Aircon not blowing cold air
Post by: chimp400 on May 04, 2017, 07:49:57 am
Its good practice to have it serviced every few years too, i usually take mine to a local kwik fit, costs £50.
Performance will go down as the gas decreases.
Wouldn't usually touch them with a barge pole but they are fine on simple air con services, and don't charge/refund if the process is unsuccessful.
Title: Re: Aircon not blowing cold air
Post by: lukemk5gti on May 04, 2017, 08:24:57 am
Scan it with VCDS.

Several people have a broken sensor at the front which you replace with a crows foot spanner, nothing to it really and costs maybe £10 or so.

VCDS will show if this has failed, it's called a N60 or N70 or G65 or something along those lines. It'll tell you on the scan.

Otherwise it could be your compressor which parts and labour isn't far off 1K so if you're not in a very hot country for most of the year I would just open the window  :signLOL:
Title: Re: Aircon not blowing cold air
Post by: pudding on May 04, 2017, 10:05:58 am
The A/C was never great on these cars even when working properly, but if the sensor doesn't solve it, my money's on a knackered condenser.   It's the front most radiator and takes a beating from stones and winter salt rots the cooling fins.

I got a quote from my dealer of £800 to replace it as the car was with them at the time for a service, which is crazy given the part is about £150 and it's just a bumper off job and replace!  Mine is utterly fooked.  All of the fins literally just crumble to dust if I run a screwdriver along it.

I'm with you mate, really tempted to just delete the entire A/C system as I rarely use it anyway, but it would reduce the car's value quite a lot!
Title: Re: Aircon not blowing cold air
Post by: lukemk5gti on May 04, 2017, 10:08:32 am
I'm with you mate, really tempted to just delete the entire A/C system as I rarely use it anyway, but it would reduce the car's value quite a lot!

Would it though?

Say you removed it to save weight and increase acceleration  :signLOL:

My buddy doesn't have it on his and so without those pipes in the way it's so much easier to work on some engine components.
Title: Re: Aircon not blowing cold air
Post by: pudding on May 04, 2017, 10:11:03 am
I'm with you mate, really tempted to just delete the entire A/C system as I rarely use it anyway, but it would reduce the car's value quite a lot!

Would it though?

Say you removed it to save weight and increase acceleration  :signLOL:

My buddy doesn't have it on his and so without those pipes in the way it's so much easier to work on some engine components.

Yeah it would if a non-enthusiast bought it!   They'd easily knock a grand off!

I bet it is!  Probably makes valve cleaning a bit easier!