Before I change the thermostat on my ABF what other reasons can cause the heating to puff out tepid air? The gauge gets up to temperature as normal, the coolant pipes into the bulkhead/matrix are both hot when running.
might be the matrix is slightly blocked, or maybe the foam has come off the flaps inside the airbox. on the mk2 if you pull the console out you can get to the air distribution box to have a look and repair in situ, the mk3 is more of a pain with the knee bar in the way so not sure if it would be possible? if the engien temps are normal then changing the stat wont do much, where does it sit on the gauge and what does the oil temp say?
All normal, temperature gets up to mid range fairly quick, oil temp standard 88-92. I am just wishing it was was as easy as have a gut feeling it is the matrix. My commute has become interesting the last few weeks!
do you notice chunks of foam blowing out of the ventsd when fan is set to full? if you do thats the flaps breaking down. otherwise yeah I'd say matrix. also check in the coolant tank, if you spot little bits of curley pasta thats from inside the matrix another clue
No, never had the foam. Last winter it was at least blowing out warm, this year quite frankly it's pathetic! I will look at the coolant tomorrow. I will look for a good guide on here for the matrix removal!
not sure there is a decent one, but I'll try and give you some pointers from memory but bear in mind I did this job near 10 years ago mind dash will need to come out, so you can get to the knee bar to pull it forwards. there are some fixings in the scuttle, which means the wiper arms need to come off so the scuttle trims can come out. with the wipers if you undo the nut but dont remove it, you can give the arms a good tug and wiggle without fear they suddenly release sending you **** over tit! then feel around, i think there were 4 fixings in total nut and bolt either side. Look at the bulkhead there are 3 nuts that hold the heater box assy to the bulkhead, plus you'll have to remove the 2 matrix pipes. 2 of the nuts are under the pipes, the 3rd is behind the coolant tank. Block the holes on the matrix with something, this stops coolant spilling inside the car later on. then go inside you'll need to pull all of the dash middle dash trims, centre console and under trays so you can release the wiring looms from the dash shell, or you may find it easier to leave the looms in place and instead unplug the looms from the fusebox. Its been a while so I cant recall exactly which way I did it I'm afraid For the dash shell you got some fixings at either end of the dash and some underneath, plus take off the wheel and stalks off it makes life easier. the fixings for the knee bar are either end and a couple in the middle to tunnel supports, undo and remove the bolt holding the steering universal joint to the column, so you dont have to worry about the shear head bolts holding the column tube to the knee bar. dont loose the spring in between! you will have to release the trims around the door opening a bit to allow the knee bar to come forwards. Oh and IIRC the outer knee bar fixings are spline or star head, so try to check before you get too far with the dash strip so you know you have the right bits! Then its a case of tease the knee bar forward a bit so you can pull the heater blower assembly enough to gain access to the heater matrix in the top of the heater box, pretty sure theres a fixing inside holding the blower inlet to the bulkhead, so release that first. sorry its a bit vague in places, as I say its been a while. I can tell you for sure is you should set aside a whole day to do the job, its a little fiddly to say the least...
