A&Q about 350Z
Q:
need some help please. its a heating problem..!! nown an again my heaters will blow hot air every so often. But sometimes when i put the hot air on it will be cold. Any ideas why its doing this? i dont think its the heater matrix it hasnt leaked or anything.
oh by the way my car is a 89 mk2 valver
A:
Defective bypass valves.
Lose them.
A:
and how do i sort this problem out then dave? i ant got a clue were to start with the heating?
cheers
A:
Defective bypass valves.
Lose them.
No, they should *never* be removed unless a new heater matrix has been fitted; the bypass valves are there for safety reasons - replace them if they are faulty.
Check the coolant level, it will go cold if the level is too low.
A:
No, they should *never* be removed unless a new heater matrix has been fitted; the bypass valves are there for safety reasons - replace them if they are faulty.
My last mk2 which I had for ten years,86 16v btw, had no bypass valves and when matrix did eventually start to go it was a gradual process not an explosion.
My present one had valves fitted and suffered from intermittent heat which was a pain tbh.
And I assume from the fact they are fitted and the service history it still has an older matrix.
I removed the valves and I am more than happy to drive it without them.
I would rather be warm than freeze my bollox off just because there is a few isolated cases which VW had to cover their ass to avoid any lawsuits.
I for one don`t always do as I am told.
Make your own mind up.
A:
dave ive mind my mind up please tell me how to take the bypass valves out, its not even winter yet and im frickin freezing already.
cheers
A:
Thing is, while VW do have an image to upkeep, I don't think they are that altruistic. There must have been enough risk (and hence, potentially "cheaper") for them to recall many thousands of cars, rather than to pay off a few lawsuits.
It doesn't have to explode, all it needs to do is rupture in such a was as to spray boiling hot water on the driver's legs.
Perhaps I am being a tad alarmist, but If you know there is a risk (however small), and are willing to live with that, then fine. I'd just caution against telling other people to remove the valves when they may not know why they were fitted in the first place, and what could happen if they are removed - especially seeing as this country is getting more like the USA where people sue over the smallest thing...
A:
dave ive mind my mind up please tell me how to take the bypass valves out, its not even winter yet and im frickin freezing already.
cheers
If you really want to, It's simple enough; just remove the two valve bodies from the heater pipes, and replace with some copper piping of suitable length and diameter. Or you could replace the pipes.
A:
If you really want to, It's simple enough; just remove the two valve bodies from the heater pipes, and replace with some copper piping of suitable length and diameter. Or you could replace the pipes.
As he says.
Pipes run from right hand side of engine block into bulkhead.
Valves are butchered into the middle of them.
BTW valves are now obsolete items.Just shows how much VW give a 5hit now.
Best to replace hoses completley but a join with some copper tube will do the job.
A:
Well i suppose you could always think of it this way...
Your driving down a busy a road in rush hour traffic in your lovely warm golf when the matrix ruptures spraying boiling water all over your nice shoes, the inside of the car mists up till you cant see a thing and then bang, youve just slammed into the car in front!
Just a thought!
A:
Well i suppose you could always think of it this way...
Your driving down a busy a road in rush hour traffic in your lovely warm golf when the matrix ruptures spraying boiling water all over your nice shoes, the inside of the car mists up till you cant see a thing and then bang, youve just slammed into the car in front!
Just a thought!
Heres another.
You are driving the 500 miles home and heater don`t work.Temp falls below zero and you die of hypothermia whilst wating for AA to appear to remove those offending valves which feck up all the time and you aren`t quite sure if your matrix is about to explode or the bypass valve are doing a champion job of saving you from third degrees burns..
As I said make your own mind up.
A:
And that is case closed!
A:
Don't waste your time arsing about with frigging valves. IT WILL BE THE HEATER MATRIX! or you hav RUN LOW ON COOLANT!
Take it from an owner of 5 mk2's with and without bypass valves. Buy a new ''edit: heater matrix'' off ebay and commence pulling your dash to pieces and replacing the heater matrix. This is actually quite a hard job if you are a beginner.
A:
try jetting water backwards through the matrix (ie connect a hosepipe to the pipes coming from teh bulkhead). This might clear it out if there is a blockage
A:
Hi folks,
Well this happened to me today hence the reason I was looking up Heater Matrix, I have an 89 GTI and today (luckily) while sitting waiting for my daughter to finish her class my heater matrix decided to spew its contents all over me.
It hit my left foot luckily I saw the steam and heard the bubble before it cameout and as stationary my feet weren't on the pedals so it missed most of me and the Mrs was in picking up the kids.
If I had been driving I would have been up ****e creek, the windows instantly steamed up and a great load of water and AF was in both footwells.
I have the bypass valves fitted and they didnt make a bit of difference and I have also suffered loss of heating etc.
The motto I would say is the heater valves aint worth nowt if your matrix is buggered (especially after the cars been sitting for a while) so get a new matrix and lose the valves is what I say.
Now I have to tackle the replacement which as I remember a few years ago was a ***** so If anyone has a step by step to refresh my memory I would be grateful.
Take care all.
A:
omg dont you some times wish you was driving a air cooled bug, no chance of water ****ing on you. hmmmm might drive the bug this winter...
Yes im with you t2000 could do with a step by step guide on that... anyone?
A:
OK, I'll attempt one - this is from memory and it's been a while since I've done a matrix, so I may miss something (sorry, no photos)...
1) Remove radio
2) Remove heater and vent control levers (these just pull out)
3) The heater panel/fan switch pops out with a little pressure, IIRC. Disconnect the fan switch and remove.
4) Remove lower set of switches and/or switch blanks in the fascia.
5) There Should now be 3 or 4 screws that hold the fascia trim panel in, these can be removed along with the two in front of the dash. You don't have to remove the steering wheel, with a little bit of fiddling, it should come out.
6) remove the 4 screws holding the heater lever mechanism (where the levers push into - you can also identify it by the two heater cables).
7) Carefully pop out the centre vents out with a small screwdriver, you should see two screws holding the vent housing in, remove the housing.
8) Remove the dash undertrays on both sides.
9) Remove gear knob, and gaiter over lever - remove the one screw that's hidden under the gaiter, and the others that hold on the centre console - I think there are two at the top (one each side) and two at the bottom (hidden at the back, one each side). And removethe centre console. Putting the gear lever in 2nd or 4th may help to remove it.
10) Disconnect the wires from the heater fan in the passenger floor well.
11) While you are still there, put your hand up by the fan, towards the inside of the car - you will find a knurled plastic "nut" - this holds up the heater box and has to be removed. It's usually too tight to remove by hand, so you may have to use a pair of pliers or similar to undo.
12) Back in the middle, there's a plastic cover in front of the the heater box that feeds air to the side vents. This is held on by 2 plastic 10mm (head size) nuts (be careful not to overtighten when replacing). It's a bit of a fiddle due to the vent pipes, but this should pull out. Watch out for "aftermarket" wiring getting caught up.
13) Underneath the heater box, there's the floorwell outlet, this is only held in place by one or two screws and also needs to be removed.
14) Pull the heater control doodah (connected to the cables) down from the dash and out the bottom.
15) In the engine bay, undo the 3 m6 (10mm head) nuts on the firewall that hold the heater box in place. These are easily identified by the fact they have large washers with a thin rubber seal washer (which usually stick to the firewall, but will come off). If the nut doesn't undo off the stud, but keeps turning, this is because the other end is coming out of the heater box. Don't worry if this happens, when the heater is out, someone can use a pair of mole grips on the inside and someone can undo the nut out in the engine bay.
16) Undo both heater pipes.
17) If all goes well, and I haven't forgotten anything, the heater box should come out. It may be a bit of a fiddle - remember to try and keep the heater box tipped backwards - or any coolant left in the matrix will pour out into the car.
18) Take heater box out of car.
19) The matrix is held in place by 1 screw (?) remove and pull back the two tabs at each side - the matrix should just lift out.
You can take the opportunity to clean out the inside of the box. The new matrix should come with a length of what is essentially draught excluder - this goes around the side of the matrix. There may also be a new seal for the pipes where it exits the firewall, if it wants to fall off, you can use a bit of tape or something to hold it in place.
Those studs that hold the heater box to the firewall, if they do come out, they can be screwed back in to it. Don't leave the studs in the firewall and try to screw them back into the box that way - it's a lot easier to remove them from the firewall and screw them back in first.
And in true Haynes fashion, fitting is, essentially, the reverse of removal.
Don't forget to top up your coolant level.
"Book time" for this is a tad under 2 hours, so would probably cost at least £120 + parts in a VW dealership. For the DIY mechanic, I'd set aside an afternoon. You may also find that wiring from aftermarket radio and alarm installs (or some bodge or another) will get in the way
Hopefully, that makes sense and is of use.
A:
well, took the bypass valves out today, and ive got heat, WINNER! what i can see is its the plastic valve that is buggerd.
A:
I've had one let go in spectacular style too so forget the bypass valves helping you. Not really that much of a problem to deal with. It was the shock of the initial noise that was the main danger, nearly jumped out of my skin!
A:
Defective bypass valves.
Lose them.
No, they should *never* be removed unless a new heater matrix has been fitted; the bypass valves are there for safety reasons - replace them if they are faulty.
Check the coolant level, it will go cold if the level is too low.
Andy
Are you saying that the new neater matrix is different in that it has some sort of a pressure release system?
A:
try jetting water backwards through the matrix (ie connect a hosepipe to the pipes coming from teh bulkhead). This might clear it out if there is a blockage
Nope. The water can pass freely through the knackered heater matrix and yet it will not work when connected up. You cant just try and blow a blockage out with a hosepipe. hose will happyly blow water out the other side of the matrix all day if you leave it running all day, and then it still won't work when you plumb it all back together again. get a new matrix.
A:
Just out of interest, VW use to give lifetime warranty on mk2 heater matrix's that didn't have the bypass valves fitted because the mk2's were recalled to have the bypass valves added but some ppeople never had the work done. I think they recently (couple of years ago) discontinued this warranty.
A:
try jetting water backwards through the matrix (ie connect a hosepipe to the pipes coming from teh bulkhead). This might clear it out if there is a blockage
Nope. The water can pass freely through the knackered heater matrix and yet it will not work when connected up. You cant just try and blow a blockage out with a hosepipe. hose will happyly blow water out the other side of the matrix all day if you leave it running all day, and then it still won't work when you plumb it all back together again. get a new matrix.
worked for me, twice.
perhaps you need a new hosepipe
A:
!
A:
my heater works for a bit when the engine is cool-warm but then cuts out when the engine gets to temperature. Is the bypass valve faulty and causing this or is it the matrix blocked-there seems to be some debate.
Interestingly I just replaced the coolant with g12+ recently and maybe it reacyed with some of the old coolant (green stuff) in the matrix gunking it up.
My bros old Audi coupe didn't have these valve things in and the matrix did blow up!- he didn't crash either or get burnt.