bluester 0 Posted December 11, 2011 hi all im after some help basicly the heater in my 16v is pants it gives out very little if any heat. im not overly technical but ill give it a go where should i start checkin. i think thermostat is worrkin ok but i have ordered a new one. the control flaps seem to be changing , it does have two bypass valves ( one metal one plastic) ive heard about drillin out these valves??? should i flush the matrix or just replace it?? any advice u guys can give would be appreciated coz it aint much fun drivin a cold corrado. :( Quote Share this post Link to post Share on other sites
fla 9 Posted December 11, 2011 does the water temp gauge rise? If not your stat is stuck open and wont give much heat into the cabin. Check water level in the header tank and see if it is not too murky, ideally should be pink and clear. If not, drain it out, flush the system until the drain water runs clear then fill with about 10 litres of white vinegar. Run teh car up to temp and then leave the vineage to soak overnight. Drain it out and flush the cooling system again about 3 or 4 times. Refill with deionised water and coolant G12++. Is there any heat from any of the other vent outlets? Quote Share this post Link to post Share on other sites
_Meth 0 Posted December 11, 2011 Its the interior heater that only blows old air? Itll be the matrix. About £40 from GSF. Best purchase youll ever make, and with a working matrix itll make your rado into a nice little sauna! Quote Share this post Link to post Share on other sites
Kempy 0 Posted December 11, 2011 Im experiencing this atm. My coolant temp isnt rising quickly or getting near 100. Oil temp is fine. Im sure its not the stat though, as I've changed the stat and the coolant and the water pump all fairly recently. coolant is getting about 90. what you reckon, matrix? Ryan Quote Share this post Link to post Share on other sites
Portent 0 Posted December 11, 2011 Wouldn't one of the symptoms of the matrix also be coolant loss and condensation in the car? Agree thought that the heaters in Corrado's are usually fantastic. It heats up and gets much hotter than my Golf (mind you so did my old mk2 Scirocco). Quote Share this post Link to post Share on other sites
Kempy 0 Posted December 11, 2011 I do get inside condensation. no coolant loss though Quote Share this post Link to post Share on other sites
fla 9 Posted December 12, 2011 i think most will get condensation because of the massive glass area - i bet you'll find the rear window regularly misted up when you first get into the car. Quote Share this post Link to post Share on other sites
Supercharged 2 Posted December 12, 2011 Condensation means moisture getting in somewhere.. No heat inside and engine is warm usually points to a seized bypass valve, new matrix and pipes required Quote Share this post Link to post Share on other sites
Critical_Mass 10 Posted December 12, 2011 Im experiencing this atm. My coolant temp isnt rising quickly or getting near 100. Oil temp is fine. Im sure its not the stat though, as I've changed the stat and the coolant and the water pump all fairly recently. coolant is getting about 90. what you reckon, matrix? Ryan Got this too Ryan, started a few weeks back (i did create a post). Temp doesnt get to 90 now, it will get to 90 (normal operating temp) in traffic, but soon drops again when on the move. It can even go down to 70. Oil temp is fine though as is MPG. I cant decide whether its the weather or the stat - stat is only a couple of yeras old. Quote Share this post Link to post Share on other sites
Kempy 0 Posted December 12, 2011 Is the bypass valve on the matrix? I know pretty much why I got moisture, not too bothered as long as I can get it like an oven in there.. Quote Share this post Link to post Share on other sites
davidwort 0 Posted December 12, 2011 Is the bypass valve on the matrix? I know pretty much why I got moisture, not too bothered as long as I can get it like an oven in there.. no, it's a combination of two units on the supply and return hoses in the engine bay just before the bulkhead connection to the matrix, it has a small pressure relief pipe connecting the two, one unit is metal the other black plastic, not needed on cars after about 1992 as the matrix was strengthened. They won't stop a matrix rotting through though (early or late), so if the car is an early one it's worth changing the matrix anyway. Oh, and I remember when I had the by-pass valves fitted new from a VW dealer, they restrict the flow of water at all times and you won't get the interior quite as hot as without them. Quote Share this post Link to post Share on other sites
bluester 0 Posted December 29, 2011 ok guys replaced heater matrix, got rid of bypass valves car heats up lovely heater is ROASTIN . only thing is screen gets oily residue while heater is on car seems to get a bit steamy inside, ive just read a post about washing new matrix to remove protective coating(which i didnt do) could this be the cause of my symptoms or i have i put i a "new" damaged matrix. help!!! Quote Share this post Link to post Share on other sites
seanl82 23 Posted December 29, 2011 I had they recalled metal and plastic bypass valves, these were faulty so did the copper pipe mod. Still I was getting very very slightly warm air, so flushed the matrix through. It didn't seem like it was blocked, as plenty of water was gushing out the other pipe. Still I was getting no hot air, so took the plunge and swapped out the matrix. I now get warm air, but I need to change the stat as well (doing it at the w.end with new coolant too). I cut the old matrix in half and it looked like a obese persons arteries! Clogged with dirty limescale and mildew and debris. Markings were 3/90 so was the original, so well worth doing IMO. Quote Share this post Link to post Share on other sites
cdem 0 Posted April 4, 2012 Bringing this back from the dead. Does anyone know if the bypass valve is still available from vw?? Quote Share this post Link to post Share on other sites
Anton Sobriquet 0 Posted April 10, 2012 Do you know the part no? I could look it up. BTW I want to swap my late heater control for the early version and I've sourced an early centre dash plastic frame to house the early control unit when I find one. Will I need to change the whole matrix as well or can I just connect the belden cables from the late control to the early control with maybe a bit of modding and keep my late matrix, which is relatively new? Quote Share this post Link to post Share on other sites
chubbybrown 0 Posted April 10, 2012 you dont need them anymore as they now have bypasses on the matrix. Most remove and fit a piece of copper pipe in its place. If its a original matrix it could have just collapsed with the rubber band swirls ( they look like pasta twists solidify and break up ) I took the dashboard out and did it that way Quote Share this post Link to post Share on other sites