Heater matrix blew-up in VR

[Rpmayne 0]

The nightmare has come true... Heater matix exploded at the weekend while trying to race a bike off the lights. 1st gear and keeping up pretty well, 6k came, second gear, POP, steam, end of race and limp off carriageway. Rider probably nearly fell off his bike laughing... if I could have seen him.

 

Got to a b&q, bought a washing machine fitting and screwdriver and bypass it, and still got the missus to her hair appointment in time.

 

I've read the american link and the knowledge base on here and leaving the dash in sounds better to me (non-air conditioning). I'm just a little worried that the knowledge base instuctions seem to imply its relatively straight forward.

 

I just want to make sure I have everything ready, like what's the purpose of the foam and should I change the cables? Also anything people have broken along the way would be helpful to try and avoid, or probably order in advance.

 

Also trying to work out what's connected to the blower box, is it just 2 cables for heat / direction, pipes in / out for coolant into matrix and the pipes to the vents which just pull off (left, right and centre)?

 

Thanks.

[KADVR6 0]

unlucky mate,

 

its not that hard to do, some people say you can do it with the dash in, but i have done 2 matrix's and both times i have had to take the dash out. i cant see how you can do it with the dash in place to be honnest.

 

while its all out, i would check the bowden cables, if they are not free moving in the plastic guides, get some new ones, they are about £30 for the 3 cables. on my first attempt at doing this shite job it took me 6 hours to do :? second time 3 hours, as for the foam mate, you will see where that sits when you take out the old matrix.

 

karl

[Rpmayne 0]

Cheers Karl, I'll order those cables (take it a VW only part). It has always felt abit tight when turning the direction dial. Going to order the matrix from GPC for £70.

 

Just off the phone to VW about the recall and apparently they were recalled to have the matrix changed but that expired 6 years ago, and mine has never been changed. They quoted £115+VAT for the matrix and £375+VAT fitting.

[craigowl 0]

Local garage broke my old heater matrix pipe (plastic, brittle - he says most are metal) when fitting Samco hoses.

They got me new matrix and I paid £45 plus VAt.

 

What a cheek VAG have!

[Rpmayne 0]

Shame they don't honour the recall later on, just wish the old owner had given it back to VW for a day. Looked like I had that super-cool air-con icing the windscreen at the time, only difference was the toxic fumes and sauna like conditions.

 

Take your point with the plastic bits, can only think the VR gets alot lotter than other VW's I had hence the extra problems. When I fitted Samco's to the top of the rad I broke the plastic and had to get a new rad, could just break bits off it by hand. The thermostat housing was the same when I took that off because it was leaking, very brittle.

[craigowl 0]

New plastic is hopefully not going to be so brittle for another few years!

Clearly, a 10-year old component with plastic parts seems to be very fragile on these cars. On my own car, the coilpack, the heater matrix and the headlight switch have all been replaced because brittle plastic which had been subjected to heat over a ten year period had failed.

[joby 0]

Ive Just done my matrix and managed it with the dash in place, just undo the nuts in the engine bay and the sneaky ones where the wiper mechanism is and pull the dash slightly away leaving it in, It can be done and at least you dont have all dash loom to put back, I took photos with the didgy camera to remember where everything went and was still left with a few screws left over. Good Luck its a horrible job :wink:

[KADVR6 0]

how did you manage that joby did you get a 2 year old to get in there?? there was no way i could get my hands in there to get mine out :?

 

karl

[SteveVPK 0]

i left my dash (early) in place when i did mine.

 

i was tight getting it out but didn't feel the need to loosen the dash or anything

 

are there any subtle differences between the early and late dash / matrix housing that might restrict access in the later dash??

 

any thoughts??

[joby 0]

KADVR6 squarepeg round hole :lol: It was tight but it came out with a struggle, probabaly better of taking the dash out but loads on here have done the job with the dash in so thought id have a go..

[jekvr6 0]

done my vr6 late style with the dash in bit of a pig to get out but went back easy dont see the problem and i have big hands think me neck hurt for a few days after !!!!!!!!!!!

[Rpmayne 0]

I am really starting to get paranoid with this car, its definitely out to piss me off.

 

As I said the heater matrix blew and filled the passenger side with water. I lifted the carpet and removed the soggy sound deadening to dry out of the car. 5 days on after bypassing the matrix (new one hasn't turned up yet) and it was still really soggy, so started to think something wasn't right. With the carpet up I found out this lunchtime that rain water is getting in somewhere behind the heater fan and dripping into the passenger well.

 

And to top it off the ABS light has started to play up. It does its normal check and turns off when the car is started, then while driving it turns on and off a few times before staying on. This is in conjunction with the red LED brake warning light flickering.

 

I cannot put into polite words how completely sick of this car I really am. By far the worst I have ever had, and I've had some bad cars. List of faults now include:

 

Blown heater matrix

Sunroof faulty

Automatic raise of spoiler faulty

ABS warning light on

RED LED brake warning light flickering

Rattle, rattle....

 

Rant over, cool blue ocean... cool blue ocean...

[Rpmayne 0]

All becomming clearer, took the passenger seat out, glove box and heater motor and arm. Water had been running in past the air intake and going all over the electrics which may explain all the failures (windscreen wipers stopped on the way home).

 

Any ideas what the three relays and controller do on the passenger side of the car?

[mattkh 0]

the passenger side electrics are the ABS . That explains the abs light.

[ZippyVR6 0]

Mine had abs probs starting the day I fixed the matrix. exactly the same symptoms as you. It self checks but when you drive off the little light pops on.

 

It turns out when the matrix was removed I dripped water on the relay on the pass side for the ABS, Have a gander at the relay behind the "undergloveboxtray" Might be a blown one.

[Jim 2]

Where the water is coming in through the heater vent under the bonnet is a fairly common spot and a classic Corrado problem! You can buy the foam gasket that seals the plenum chamber cover, from VW for not too much money! I had to replace it on my first valver as it was totally shot though not the cause of my water leaks in the end..

[Rpmayne 0]

Nice one, at least something is starting to make sense. Maybe why the red LED brake warning light had started coming on aswell. Seems that the heater motor leak was happening before the matrix let go.

 

Windscreen wipers are intermittently working now, had to drive 30 miles in the rain without them working, then when I got to a MacDonalds drive-thru near home they worked again.

 

VR sounds cool without the heater motor ducting, trying to find some positives.

[Rpmayne 0]

Got the heater box out without removing the dash and speedo. Had to strip the carpet because it was saturated but otherwise didn't go too bad and I can still use the car.

 

I've attached a couple of pictures for interest, the inside of the heater box was a right state, definitely need to replace all the foam on the flaps, and the belden cables were well tight.

 

Any ideas what foam to use, where to get it from?

[Rpmayne 0]

I've almost got all the bits now to put the matrix back in. When I picked up the box this morning a foam-like washer fell out of somewhere. I faguely remember someone mentioning these but I can't find the post. Any idea how many there should be, or what their purpose is?

[lj16v 0]

Mate,

 

Keep posting pics as i'm doing mine and i need all the help i can get!!

Took the car to my garage with most of the under-dash, glove gox, centre console out so i wasn't paying them to just unscrew panels, they had a look at it and said that as i had got that far i may as well finish it my self! i think they are more confident in my ability than i am!!

The bit i am struggling with at the mo (have been following the wiki guide from this site) is removing the heater motor and arm before i can pull out the heater box in the center (behinde the center console) there seem to be a few hiddden little metal clips conecting the arm bit to the heater box in the centre, think i need to get a small kid in there. i have undone a nut in the scuttle which i assume is holding the top of the heater motor, is that right? Have also undone 2 of the 3 nuts in the engine bay, one for the heater motor on the passenger side and the top one for the heater box in the center of the bay, unfortunatly the lower one down by the exhaust has got rusted up (probably due to being nearer to the road) and i can't release it at the moment, any ideas? is there any way i can get hold of the other end of it in the car while some one else turns it from the engine bay side? (its spinning at the moment) Should i hack saw it off??!

 

I am guessing that when i have got the heater box out it will be slightly easier from there on.... how are you getting on, anything i need to know?

 

cheers, laurence.

[Rpmayne 0]

Hi Laurence, will keep taking pictures and posting. Got a few answers to your questions that will hopefully help:

 

Separating motor arm from box

I separated the motor arm from the box before removing the box as you say. I think there were 6 clips, two front, two back, and ones at the top and bottom. After taking the passenger seat out I layed on my back looking up behind the arm / box join and used a long flat screwdriver to get under the clips and flicked them off.

 

Nuts in engine bay

The nuts you should have removed in the engine bay are 10mm on big washers (rubber backed). Two in line with the heater box (middle of bulk head) and one behind the coolant tank holding the middle of the motor arm.

 

The lower in-line spun on me aswell. I dremelled flats on the unthreaded part and used that to stop it spinning while undoing the nut. As it turned out the spinning (nut locked to thread) just unwinds the other side from the heater box. You could just spin it until the heater box goes loose, remove the box then get someone to hold the other side which has a hex to hold onto. Loads of WD40 used obviously.

 

From there

I can't remember exactly but from there you should be able to see what else needs to be removed. There is a tricky screw holding the windscreen air duct on the right. I've just found long screwdrivers have got to everything. Didn't have to remove the driver side air duct or the speedo, just the speedo surround.

 

Let me know if you get stuck on anything else, I'm hopefully going to be at the stage of putting it back in at the weekend after getting fixings from VW, new cables (unbelievable difference) and foam for the heater flaps from Maplin. Plus a few bits of trim that have been broken over the years.

 

Cheers, Richard.

[lj16v 0]

Richard,

 

Finished mine yesterday, took bloody ages!, really awkward with big hands! Anyway it seems to be working fine and i've probably saved a few hundred quid by doing it myself.

My new matrix actually came with a sheet of 3mm foam just big enough to re-cover the flaps in the heater box, mine hadn't disintegrated badly but i fugured that as it was out i may as well do the job properly! I did't replace the bowden cables as they seemed fine, just gave them and all the moving parts a good lube.

 

Now just waiting for the carpet to dry out, got a de-humidifier running in the car, should suck it all out!

 

Thanks to you and everyone else for their advice :)

[Rpmayne 0]

Well done mate, haven't quite got all mine together yet (got to lift the carpets again because I forgot those sand-filled mats) but the dash is already sounding alot more solid.

[BigTartanJudge 0]

Hmmmn, this is what I can't understand with mine tbh, was sure it was the heater matrix, with the amount of sticky water soaked into the passenger side footwell and towards the back seat. The coolant level is also low in the expansion tank and the level warning light illuminates after 10 mins of driving. Have checked all the ducting (cleared of debris) and door seal / membranes (intact). No steam coming through the vents in dash etc either but occasionally the windscreen does steam up badly.

 

I cleaned and dried the mats and soaked up the excess water in the footwells with newspaper and then disposed of the sodden paper and left her to sit. Haven't driven her in ages, then checked the interior passenger side last night and it's all bone-dry now ?

 

How is this possible, is it just because the system is not pressurised and the matrix is not under pressure so won't be able to leak into the interior at the moment ? Will it just start to leak again and the interior passenger side become sodden again if I start to drive it again now ?

 

Any help / advice appreciated !

[Rpmayne 0]

Does sound like the heater matrix with the sticky water, no other leaks and coolant disappearing. Mine turned the car into a sauna when it let go so I had no doubt.

 

As I see it the collant feeds to the heater matrix are the highest part of the system, so with the engine stopped the coolant from the matrix could have already gone into your car which you have dried.

 

Once you restart your car the water pump will feed the remaining coolant system water back into the matrix, so once coolant is present again under pressure it will probably leak.

 

I'd probably try lifting the carpet and sound deadening from the passenger side, drive the car about and look for the water before it soaks everything again.