I recently replaced my heater matrix in my Series 2 205 GTi and I thought I'd pass on some observations.


The original radio/deck was dead when I bought the car (as they often seem to be) and a replacement deck I had fitted quietly died after not much time. It became apparent that the heater matrix had been leaking and the recent cooling system upgrade I had performed which included moving to 'red' coolant had accerbated the problem... seems its a bit more 'slippy' than the old green glycol blend.

I was in the process of fixing a few minor things in the dash like replacing clock bulb etc, which needed some of dash panels removed. I attempted to following the minimal Haynes instructions to get to the heater but stopped part way as I soon realised I would be back to the firewall by the time I had done their bidding!

A quick Google offered up the suggestion of simply removing the main RHS underdash panel (3 or 4 screws) which then exposed the side of the heater matirix.

Still it wasn't a lot of fun standing on your head trying to work in a fairly inaccessible place, but getting the matrix and pipes out wasn't too bad in the scheme of the things. Turns out the reason it was leaking was probably not so much a leak in the core, difficult to tell as it looked fairly tragic, but some muppet who had it out at some point and lost one of the screws which held the metal pipes into the matrix body. So on one pipe, there was only one screw and so the locking plate wasn't exerting even pressure on the pipe/o-ring. Damn.

The replacement Valeo unit came with proper Hex head setscrews as opposed to the PH version of the previous unit. I though great, I can at least torque it up a bit to ensure the o-ring is tensioned against the flange better. But of course the accountants got involved and decided to use screws that were just long enough once installed, but buggered if I could get both sides started... hours go by. I bought some longer screws, 5x20 and bingo... screwed in, in less than a minute... and could even add some spring washers into the solution.

The longer 5x20 screws had an 8mm head compared to the original 5x16 screws with a 7mm which offered a little more fun in the very constrained space of the rear screws, but victory in the end.


Series 2 205 GTi heater matrix replacement-heater-matrix.jpg