heater problem

[raj]

i have a mk2 8v GTi, my problem is my car does not blow out hot air only cold. i have cheaked my matrix not leaking. can anyone hepl?

[Gambit]

aye, you've probably got an airlock

make sure your heater setting are set to max heat.

flush the system

refill it

let the car idle with the expansion cap off until the fan kicks in or the water boils

turn the engine off, top up the coolant level and stick the cap back on tight

[raj]

cheers mate!

[richandhazel]

Could be an airlock as 'Gambit' suggests. The other thing worth checking is your bypass valve. There's been a few threads recently concerning poor Mk2 heaters where this has come up.

[willy368]

Raj,  Listen to a bloke who knows,  in front of the heater matrix in the engine bay are the two rubber tubes which come from the bulk head.  Attached to the tubes is a small alluminium type 3 way valve,  go to a scrappy, or indeed to VW and buy one of these small devices.  Replace your valve with the "new" one and your problem should go away.  To give you a bit of history, last year I replace my heater matrix when I had the same problem as you, nightmare job working upside down arms all scratched to pieces.  When I finished the job the heater was still cold.  ?2.50 from a scrappy for the new valve..... Car was Roasty Toasty.  Let me know how you get on.

[richandhazel]

Yep, we're both talking about the same thing, bypass valve, 3 way valve........worth looking at.

[Blue MK2]

I dont have one. You recon i should get one on my 8v?
Do you install a valve on both tubes that go into the bulkhead?

[raj]

thanx everyone for your advice much appreciated