If your 6N polo over heats, or the temp gauge is only at 90 when in traffic the answer to the problem is below.

The most common cause is the thermostat housing bridge part braking, as in the pic (the top one is the good one) :

Take the pipe off the thermostat housing that goes to the bottom of the radiator and check this. Easy to replace, just two 10mm bolts.

When refitting make sure that the pin on the thermostat is short, otherwise it will not go back together with the pin out.

VW part numbers:

Thermostat

ADX AEA and AEV: 044 121 113 £22.35 +VAT

All other engine codes except AJV: 032 121 110B £16.25 +VAT

Bridge Housing

ADX AEA and AEV: 032 121 121 A £4.75 +VAT

All other engine codes: 032 121 121 J £10.60 +VAT

'O' ring for all models: 032 121 119 H £1.65 +VAT

Hope this helps!

Finally!! and with photos. People just pershume when you roughly say where something is others will get it! :)

Thanks for this

Why isn't this a sticky, its the only one that has made any sence

make this a sticky cos this problem has just come up on my polo thanks

yeah i got this prob atm, when i take the water bottle top off then turn the car on, the water bubbles up and over flows, is that the thermostat, plus the fan is not cuttin in and fuses r ok.

yeah i got this prob atm, when i take the water bottle top off then turn the car on, the water bubbles up and over flows, is that the thermostat, plus the fan is not cuttin in and fuses r ok.

If the thermostat isn't opening the hot coolant won't reach the fan switch in the radiator. Does the hose from the bottom of the radiator get hot? If not sounds like a thermostat related problem.

i have sorted it thx to u, lmf- luton motor factors quoated me 73 quid, i thought fuck off, then got it from gsf for 13 quid all in, fitted and fine fan cuts in and stayed at bwt 80, thx again

great thread mate, really helpful. my car started overheating a few days ago, got up this morning , whipped the housing off and sure enough it was broken. gona order the parts now.

I had this problem, made a quick fix by heating up a small nut that wouldn't allow the pin to go through, and then melting it into the bridge part. Seemed to work alright.

thankyou so much for this post.

this is aexaclty what happened to me today .... coolant spews out everywhere when the engine is on .. bottom house stays cold and no fan on... will change the thermostat 2mora :) thanks for this, its a great help.

Chris

Edited 31 October, 200916 yr by parfay_2009

my car stays stone cold when running lol.

temp only gos up after you have stoped and have the engine off for a while then it gos back down to nothing on the gauge after a few mins,

or if you stop in traffic it clibes up realy slowly, but drops asoon as you get going again

i think the thermostat might be stuck open, could it be anything else?

my car stays stone cold when running lol.

temp only gos up after you have stoped and have the engine off for a while then it gos back down to nothing on the gauge after a few mins,

or if you stop in traffic it clibes up realy slowly, but drops asoon as you get going again

i think the thermostat might be stuck open, could it be anything else?

Or the housing has broken, the whole point of this thread!

Thanks so much for this, the better half's 6N2 began belching steam last week, limped it home after letting the engine cool and now after just over $100 Aussie of parts and coolant, we're up and running. Sure enough, the thermostat pin had punched right through the bridge. Also, the OEM part numbers were a godsend since the dealership refused to help out without a chassis number. When presented with their own part numbers they couldn't refuse.

Is the temperature supposed to fluctuate when you're driving? When I bought my car it used to hold rock steady at 90°C and was pretty quick to get to that temperature. Since having the thermostat and housing changed it takes ages (about 10 mins of driving) for the engine to get to 90°C. Then after about another 10 mins of driving, the temp mysteriously drops to about 80°C, before slowly climbing back up to 90°C...

So basically, is this normal?

Is the temperature supposed to fluctuate when you're driving? When I bought my car it used to hold rock steady at 90°C and was pretty quick to get to that temperature. Since having the thermostat and housing changed it takes ages (about 10 mins of driving) for the engine to get to 90°C. Then after about another 10 mins of driving, the temp mysteriously drops to about 80°C, before slowly climbing back up to 90°C...

So basically, is this normal?

She should be rock steady! Had same problem that temp would fluctuate during driving between 70C and 90C. Beside that I had trouble at cold start during winter. Thermostat was ok, temperature sensor was the problem! Replaced it and again my temp is rock steady.

http://www.clubpolo.co.uk/forum/index.php?...100712&st=0

I will replace this to see if it works.

Mine would shoot up temperature then blow out. I replaced the thermostat, didnt check the bridge housing. The top pipe goes hard and gets hot and the temp just keeps rising. happened the other day on the motorway.

AA chap said he reckons HG, do you lot reckon its just the bridge? from memory i think it was broken!

cheers in advance!

Been having a mare with my car. recently put new alternator and belt, new thermostat, oil and filter and the problems still keep coming!

Any help would be greatly appreciated!

Harry

Hey guys,

Before I read this thread I had already bought a new thermostat off Ebay, got it with the O ring for £6.50 all together + packaging..

Here's a picture and the link if it's any use to anyone else :-)

Tommy.

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?Vie...T#ht_1672wt_907

Had the under heating problem, bought new thermostat, fitted, old one was not there, now over heating, didn't realise before that the hole shouldn't go right through...

Very helpfull thread!

Had the under heating problem, bought new thermostat, fitted, old one was not there, now over heating, didn't realise before that the hole shouldn't go right through...

Very helpfull thread!

I had the exact same problem mate! nothing in there to start off with. How have you gone about this? It just overheats like crazy.

cheers

Well I've ordered a new cover off of Ebay, it hasn't come through yet though. Just noticed I've ordered one for a diesel and it has a different part number. Ooops.

Anyone here know if it'll probably fit, can't imagine the cooling system will be much different between them?

Well I've ordered a new cover off of Ebay, it hasn't come through yet though. Just noticed I've ordered one for a diesel and it has a different part number. Ooops.

Anyone here know if it'll probably fit, can't imagine the cooling system will be much different between them?

Ahh cool, yeah I literally just noticed mine has a hole in it too! so the new thermostat has nothing to push against when it's in place. I'll be ordering one nowwww, and that sucks you got the wrong one mate. Fingers crossed, they might still be the same.

Cheers.

Thought I'd just say,

if anyone else has had this problem, and the pin is sticking out way too far for it to fit in the housing, put it in a cup of boiling water, and within seconds you can take it out and push the pin all the way back in.

cheers.

Part came through today, as expected it's the wrong one, there isn't a bridge in there at all.

Anybody need a thermostat cover for a 1.7 - 1.9 diesel 96- polo? send me a pm

Edit: Volkswagen still store these, got mine today for £13 odd inc VAT.

Be careful when re installing the cover, I managed to strip the threads with a 3" ratchet just as it started to give resistance and another thing is try to tighten them up in half turns, with the o ring after tightening one screw up the cover was on the piss with the other screw tight

Edited 18 November, 201015 yr by Little Gap