I have a weird issue with my '96 Punto 55. Ever since I have owned it I have had an issue with the front screen misting up badly. I read about the problem being caused by the heater matrix leaking, but as the engine runs fine and only loses a small amount of coolant weekly, I have put up with the problem till now.

A few days ago I found a sizeable puddle of anti freeze in the passenger footwell so I went online and ordered a new heater matrix and some jubilee clips for the hoses as I thought " well tha she blows"


The weird is that after that initial puddle, the carpets have now dried out. the windscreen misting is all but gone, and the heater seems to be working better than it ever did!! I have checked the coolant level over the last few days and that doesn't seem to have dropped either!


Now obviously the only place the antifreeze puddle could have come from is the heater matrix .... so why isn't it still leaking? It's almost like the matrix had a huge puke and now feels better! But logically there must be a hole in it or the coolant would not have leaked out in the first place.


I am going the strip out the dash and replace the matrix when the new one arrives but I was just wondering if anyone has seen this whole issue before? I almost feel like leaving it alone now I can see out of the windscreen again.


Any comments? ......

perhaps some gunk got pushed threw the hole and it leaked till another gunk plugged the hole and stopped the leak, when was the last time you changed antifreeze

use distiled or deionized water when mixing it with antifreeze

Yeh Flisko ....that idea works. Very logical. I have only had the car since March this year so anti freeze is as it came. I will replace the matrix as soon as.I was just intrigued on how it seems to have fixed itself .....

give the whole system a flush, could be person before stuck some crap in like rad weld or k seal that has resealed the hole temporary, best to get it out and do the job right

Just an update to this thread..... I replaced the heater matrix yesterday and it's not a job I want to do again! Took 7.5 hours start to finish (with copious ciggie and swearing breaks). A few points for anyone attempting this job:-

1) the upper shroud on the steering column is held by 2 x 10mm allen screws which are removed from the underside of the shroud and are well hidden. My upper and lower shrouds are held together with duct tape now (tastfully done of course) as I thought it was just stuck and ripped it off breaking the brackets
2) You don't need to remove the steering wheel as per Haynes (but you need to undo the 4 10mm bolts and drop the column)
3) If the fascia won't come away after you have removed all the bolts (3 long bottom of windscreen, 3 each side along the bottom (1craftily hidden behind a plastic cover inside glovebox) you just have to use brute force. It will come away eventually.
4) Same with the heater box/fan. Mine was almost welded to bulkhead soundproofing
5) The cheap and nasty hoseclips on the heater pipes in engine bay are a bugger to remove. Mostly because they are so difficult to get to. I used a very long thin screwdriver and just kept levering the clips under the "bulges" until they finally let go
6) Make sure you label all the electric plugs you disconnect. I didn't and regretted it! (got everything back where it should be more by luck than judgement except the headlight levelling switch plug which I still haven't located!)


It's a nasty job which you should allow a full day for. I will drive the car carefully for next few days monitoring engine temps and coolant levels in case of the dreaded air locks. I did fill the new matrix with coolant before fitting it and sealed the ends of the heater pipes with rubber bungs to minimize the risk of getting an airlock. The heater gets nice and hot and no signs of air from the bleed screws so hopefully it will be alright.


I would hate to think how much a garage would charge for this job as even a skilled mechanic would be at least 4 hours doing it. At the end of the day it cost me £13.11 total for the job,the matrix came from Euro Car Parts (pt no 214650021) at £9.54 and the rest was for a couple of jubilee clips for the heater hoses. I reckon a garage would charge at least £250.

There's an old saying (of many cars) that the heater matrix is suspended from a wire on the production line, and the rest of the car assembled round that!