Drive belt tensioner failed

[FirstG]

Hi, 

2011 2.0 tdi 170,  Has anybody suffered from a failed drive belt tensioner? First thing that happened to me was loss of power steering, then a minute later a warning came up saying the battery was not being charged & a battery symbol flashes on & off. I haven't checked the belt yet but it points to this being the problem. If anybody has managed to sort the problem please let me know what you did & if it can be done easily enough as  DIY project.

[FirstG]

Update,

I've just inspected & found the V belt to have split in half & snapped. It looked to be in pretty bad shape. Its been squealing a bit recently & the AC was regassed two weeks prior & has been on most of the time putting more strain on an already old & 'past it' V belt.  I'll get a new one fitted & report my findings back.

[FirstG]

My local VAG independent, Chris Umpleby fitted a new belt & confirmed no issues & no damage. Just an old belt that had split into slivers & failed due to being old...

[Steve Q]

Glad you got sorted 🙂

[FirstG]

I'm following up to my own post in case anybody searches for it & needs some answers & it's polite IMO.

Yet again my drive/serpentine/fan belt had an issue. It jumped off this time due to a badly failed tensioner. I took it back to my local VAG indy, Chris Umpleby, & he confirmed the tensioner had a fit & fell apart. It half chewed & subsequently threw the belt. He also diagnosed a clutch pulley on the alternator was bad. 

Anyway, all this was replaced & it made me wonder if the bad tensioner & the bad pulley could have an affect on the AC compressor & how consistently it works. If the belt pressure alternates from having slow to a normal amount of tension due to failed components, would the AC be hit & miss?  Which in all honesty, it has been hit & miss recently. I only got the car back today & I haven't had the AC on. Hopefully the new belt, tensioner & clutch pulley will contribute to making the AC work efficiently.

There is refigerent in the system because it does blow cold but I noticed when on a very recent long journey at higher speeds the AC did not blow as cold as expected. I suspect the belt was slipping causing the compressor to not engage properly?? I'll post again after I drive it for a prolonged period.

[cliffcoggin]

16 minutes ago, FirstG said:

I'm following up to my own post in case anybody searches for it & needs some answers & it's polite IMO.

Thank you. Politeness is a rarity here.

[FirstG]

Yeah.....

I've been driving around in the 4 day UK summer we're currently having!!!  Yes the battery charges up way faster the fan/serpentine belt runs very quietly but the AC is still very much hit & miss. Sometimes dry & cold air & then it switches to damp muggy air & the odour changes to musty & then back again to frigid air. Could it be a bad AC pressure sensor telling the compressor to switch itself off?

I'm not expecting any assistance/help back as that seems to be the theme but I will update my findings. Why else do we have these forums??

I will check the fans are working when the compressor clutch engaged etc & see if I can resolve the issue without too much expense.

It would be nice for some input/help from another kind helpful member who has had a similar issue. We all live with some hope for mankind!!!

[cliffcoggin]

2 hours ago, FirstG said:

I'm not expecting any assistance/help back as that seems to be the theme but I will update my findings. Why else do we have these forums??

As you know from your own involvement in this forum, most members are only interested in solving their own particular problem without a thought to giving anything in return, so it's always refreshing to see somebody return and offer their experiences.

Regarding the hit-and-miss musty damp air, have you checked that the condensate outlet from the heat exchanger is open? It is supposed to allow the condensed water to drain out, but can become blocked with dirt, leaves, mould etc. leading to damp air air or even water in the cabin. I have no idea where it is on a A6 or what it looks like, but there will be one. The outlet on the Ford I had many years ago was a steel pipe with a split rubber bulb on the end. The idea was for the split to open under the weight of water, and then close of its own accord, though I daresay many different designs will exist.

[Magnet]

Many thanks indeed Graham.

For what it costs, I would be first changing the pressure sensor, since was a well documented issue.

Kind regards,

Gareth. 

[FirstG]

Hi Gareth,

Yes I did think to try the pressure sensor first, an indy VAG mechanic in Manchester reckons it's the compressor. My thoughts are why would it still blow cold when the car is at a stand still? The compressor clearly works, it's almost as if it's been told to switch off especially when the car is moving at speed. Which is why I agree that the first port of call is the pressure sensor. I checked the belt area when it was running cold but could not see the compressor so I couldn't check if the clutch was stuck out. Unless of course it doesn't have a clutch, being an Audi!!

I have no water in the footwells so I'm convinced the drain isn't blocked.  It has to be a sensor. Does anyone know of any other sensors in the AC system that could affect it in such a way? Or add to the complexity.

My last car, a SAAB 9-3 2.8T aero, had no issues with its AC & was much older, yeah it was regassed twice over the 7 years I had it, but always delivered a chill in the rare British summers we have in the north!!

[FirstG]

Continuing.... it tends to blow cold when out of the sunlight... I picked my son up from work yesterday evening & it blew cold continually, maybe its a faulty sunlight sensor? I can't find many threads anywhere other than 1 saying its purpose is to detect if sunshine is giving extra heat to the car & make the AC work extra harder. My AC seems to do the exact opposite!!  

[cliffcoggin]

22 hours ago, FirstG said:

My last car, a SAAB 9-3 2.8T aero, had no issues with its AC & was much older, yeah it was regassed twice over the 7 years I had it, but always delivered a chill in the rare British summers we have in the north!!

Well it was built in Sweden at a time when quality still meant something. You might be surprised to know that Sweden can have hotter summers than we do so aircon had to be reliable.

[Magnet]

Thanks Graham,

My take on it is to renew the pressure sensor and hope it solves the problem. If not worry about any other possibilities only at that point. 
Kind regards,

Gareth. 

[FirstG]

Pressure sensor changed, going to take it for a run & see how it performs & use it through the week for work to see if, 1 it works & 2 it works consistently in different conditions ie low speed, high speed etc.

I'm thinking it may need regassing....  I will report back 

[FirstG]

Well it's been a couple of weeks since fitting a new AC pressure sensor. I don't think it was the issue, whilst we haven't had much of a summer in West Yorkshire the AC still does not blow constantly cold air. I think it may have not been evacuated properly at the last regas. This was done through Groupon at ATS in Cleckheaton. It may be that it was done too quickly or not correctly & not enough gas was put back in. 

I'm gonna try find a specialist AC service mechanic to see if it can be looked at properly. I'll report back.